Advantages of straight weight oil

Posted by: Now

Advantages of straight weight oil - 03/20/14 06:27 PM

New member first post. I've been working in the industrial field since 1980 and was greasing cars and trucks since age 13 using the old huge single cylinder lift.
I did do a search.

Topic should read disadvantages of multi weight oil. What qualities does the oil forfeit to become multi-weight?

I know about cold starting and flow capability of multi-weight. I always allow my engines to warm up, before raw-hiding them.

Any links welcome.
Posted by: Hyde244

Re: Advantages of straight weight oil - 03/20/14 06:34 PM

Since straight weight oil doesn't have Viscosity Improvers, it will not sheer as readily.

However, the advantage of having a lower viscosity at start-up outweighs this factor, which is why multi grade oils are recommended for all modern light-duty engines. Multi-grade also has the benefit of better detergent development; that is, Pennzoil and Mobil 1's detergents are not seen in any single grade oils.

Simply put, multi grade oil carries many performance improvements that makes it the superior oil.
Posted by: Rand

Re: Advantages of straight weight oil - 03/20/14 06:39 PM

if the multigrade oil has no,a small amount of , or high quality VII then then there is really no advantage to single grade motor oils in most applications.
Posted by: fdcg27

Re: Advantages of straight weight oil - 03/20/14 06:51 PM

Even the straight grades aren't really straight.
The basestock will have its own VI, so even a straight grade will be thinner at cold start than it's SAE viscosity grade might lead you to think.
In your climate, you could probably run a 20W-20 winters and a 30 in summers with no ill effects in most engines.
There was a member here some years ago who ran an Amsoil straight 30 syn in a modern car (It was the old FWD 300M IIRC) with good results and we have at least one other member who ran 30 grade Delo for some time because he got it really cheap on clearance. He had good results as well.
I've sometimes thought that a few runs of a straight grade in a beater followed with a UOA might be very entertaining.
Want to try it?
Posted by: bullwinkle

Re: Advantages of straight weight oil - 03/20/14 06:55 PM

Been running Delo 400 straight 30 in the GMC in my sig since AZ blew it out for 99 cents/gallon-other than not being able to start it unplugged this winter one morning (-15 degrees F.), no problems.
Posted by: Hyde244

Re: Advantages of straight weight oil - 03/20/14 06:57 PM

^ Any noticeable time length in start-up?
Posted by: Zaedock

Re: Advantages of straight weight oil - 03/20/14 07:15 PM

Ahh, the good old Delo SAE30 days. I'm down to two gallons!


I started both diesel and gas engines below freezing. I didn't notice any change in cranking time.
Posted by: CourierDriver

Re: Advantages of straight weight oil - 03/20/14 07:32 PM

In the 50s and early 60s that is all we had,,,never lost an engine in Tennessee over it,,,go figure.
Posted by: gfh77665

Re: Advantages of straight weight oil - 03/20/14 07:54 PM

I have:

1) Mixed 30 with 10-30 in varying amounts
2) Ran straight 30
3) Even ran straight 40 (Im in TX summer and oil was almost free)

My 1997 Chevy truck never...even...noticed.
Posted by: JHZR2

Re: Advantages of straight weight oil - 03/20/14 08:39 PM

In an engine that is run for very long times, essentially steady-state, I dont see a reason to use anything different. Uses like that might be boats or cross-country applications like greyhound busses.

IMO the shear-stability and better flow of a multigrade makes it the better option, these days at least. In some places with high continuous ambient conditions, it still may be the best.

If I truly drove non stop a lot, and could find a good monograde, I suspect it might be an interesting application. Perhaps ditto if I were driving a police car or taxi. For anything else? Not sure unless it was really needed for some other reason, and you didnt want to go syn.

Here is an interesting little thread I had a few years ago about MB's design considerations for monogrades:

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2325682&page=all
Posted by: turtlevette

Re: Advantages of straight weight oil - 03/20/14 08:52 PM

Originally Posted By: Zaedock
Ahh, the good old Delo SAE30 days. I'm down to two gallons!
I started both diesel and gas engines below freezing. I didn't notice any change in cranking time.


Do you think it lubricates as well as a 0W in the first 10 minutes after startup below freezing?


Originally Posted By: gfh77665
I have:
1) Mixed 30 with 10-30 in varying amounts
2) Ran straight 30
3) Even ran straight 40 (Im in TX summer and oil was almost free)

My 1997 Chevy truck never...even...noticed.


I don't mean to single you out...

Why do you think it was free? We keep hearing things like "my engine likes it" or "my engine doesn't like it". There are all kinds of placebo effects going on here.

We could drain all the oil out of our engines and they'd start right up and run well for some time. Is that a like or dislike?
Posted by: artificialist

Re: Advantages of straight weight oil - 03/20/14 09:10 PM

Briggs And Stratton and Tecumseh engines often recommend using SAE30, and in extreme cold, multigrade syn is recommended.

Yes, there is Amsoil SAE30. It got the name because much like other SAE30 oils, there are no VIIs. However, since PAO basestocks already have a great viscosity index, some people have compared the oil to a 10w30.

A while ago, I did some research on the 1970s Pontiac 301 turbo engine. It called for SAE30 in all temperatures, and some people have said that the multi-viscosity oils would have a higher NOACK, and with the added heat of a turbo, that could be a huge problem.

Another reason SAE30 has an advantage over multigrade oil is that the API does not limit SAPS content the way it does in multigrade oils. That in mind, you would need to do a VOA to actually know if it is a high SAPS oil.
Posted by: Shannow

Re: Advantages of straight weight oil - 03/20/14 09:12 PM

Originally Posted By: JHZR2
In an engine that is run for very long times, essentially steady-state, I dont see a reason to use anything different.


Also without the temporary shear of VIIs (I believe that) you can run thinner straight weight KV100s than multis...

As an example, this makes sense...moreso to me than a 0W-20 in a 10W-30 application.

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1174209
Posted by: Shannow

Re: Advantages of straight weight oil - 03/20/14 09:14 PM

Originally Posted By: turtlevette
Originally Posted By: Zaedock
Ahh, the good old Delo SAE30 days. I'm down to two gallons!
I started both diesel and gas engines below freezing. I didn't notice any change in cranking time.


Do you think it lubricates as well as a 0W in the first 10 minutes after startup below freezing?


Do you think that someone who doesn't ever SEE freezing needs any more than SAE30's cold properties ?
Posted by: gfh77665

Re: Advantages of straight weight oil - 03/20/14 09:23 PM

Originally Posted By: turtlevette
Why do you think it was free? We keep hearing things like "my engine likes it" or "my engine doesn't like it". There are all kinds of placebo effects going on here.


No placebo effect here, I am referring to the clearance price I bought it out at. I bought 200+ qts for less that $150, when some convenience stores were closing out. Most all of it was Mobil 5000 or PYB.

The majority was 5-30 and 10-30, but it did include about 15-20 30's and 40's.

I use the multigrades in the winter, and use up the straight weights in the TX summer.
Posted by: Shannow

Re: Advantages of straight weight oil - 03/20/14 09:32 PM

turtlevette seems to have a misunderstanding of the "placebo" effect, thinking that the "placebo" effect is imagination, when it is actual, clinical changes, brought about by something that shouldn't have brought such changes.
Posted by: Zaedock

Re: Advantages of straight weight oil - 03/20/14 09:35 PM

Originally Posted By: turtlevette
Originally Posted By: Zaedock
Ahh, the good old Delo SAE30 days. I'm down to two gallons!
I started both diesel and gas engines below freezing. I didn't notice any change in cranking time.


Do you think it lubricates as well as a 0W in the first 10 minutes after startup below freezing?



Yep. It did a fine job too.

There is more to start up wear than oil flow. Delo SAE30 has a pour point of -24*F and behaves more like a 15W30.

10 minutes? Is it ideal, no - but nothing is going to blow up.

Posted by: turtlevette

Re: Advantages of straight weight oil - 03/20/14 09:40 PM

Originally Posted By: Shannow
Originally Posted By: turtlevette
Originally Posted By: Zaedock
Ahh, the good old Delo SAE30 days. I'm down to two gallons!
I started both diesel and gas engines below freezing. I didn't notice any change in cranking time.


Do you think it lubricates as well as a 0W in the first 10 minutes after startup below freezing?


Do you think that someone who doesn't ever SEE freezing needs any more than SAE30's cold properties ?


Yes. Absolutely.

I think I see a pattern here. You have different "fan clubs" here. Thick oil, thin oil, and no/low VIIs. There's really no changing of anyone's mind that's going to happen.
Posted by: Shannow

Re: Advantages of straight weight oil - 03/20/14 09:47 PM

No, please explain how oil that's flowing in seconds is going to protect more than oil that's flowing in seconds...I'm interested.
Posted by: turtlevette

Re: Advantages of straight weight oil - 03/20/14 09:55 PM

Originally Posted By: Shannow
No, please explain how oil that's flowing in seconds is going to protect more than oil that's flowing in seconds...I'm interested.


Unless the oil is in its viscosity sweet spot its in its "plastic" state and does not lubricate as well.

Also, do you think oil in a syrup like state is going to sling properly to lubricate the piston and rings?

Hello?
Posted by: Shannow

Re: Advantages of straight weight oil - 03/20/14 10:03 PM

Sorry, as usual, you are going to have to dumb your technical talk down to third grade level....

"syrup", "sweet spot", "sling" and "plastic" are new ones to me.
Posted by: turtlevette

Re: Advantages of straight weight oil - 03/20/14 10:07 PM

You also have cavitation issues with thick cold oil.
Posted by: gregk24

Re: Advantages of straight weight oil - 03/20/14 10:07 PM

The only advantage I can think of would be better shear stability, which is not a concern in modern multi viscosity oils so shear stability is a moot point. The modern multi weight oils are without a doubt the better oil
Posted by: jrustles

Re: Advantages of straight weight oil - 03/20/14 10:09 PM

>plastic
>syrup like state
>non-freezing climate

Slow down turt, think about what you're trying to say. Your imagination is running wild with all that sensationalism.

Originally Posted By: turtlevette

Yes. Absolutely.

I think I see a pattern here. You have different "fan clubs" here. Thick oil, thin oil, and no/low VIIs. There's really no changing of anyone's mind that's going to happen.



When you find yourself part of a fan club, by perhaps being hyper-reactional and anti-the-other-guy to people who disagree with your way of thinking for instance, then you know getting off course. Just accept that other people's reality will not correspond with your imagination. smile
Posted by: Shannow

Re: Advantages of straight weight oil - 03/21/14 03:03 AM

Originally Posted By: Shannow
Originally Posted By: JHZR2
In an engine that is run for very long times, essentially steady-state, I dont see a reason to use anything different.


Also without the temporary shear of VIIs (I believe that) you can run thinner straight weight KV100s than multis...

As an example, this makes sense...moreso to me than a 0W-20 in a 10W-30 application.

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1174209


For those that haven't looked at the link, GMan ran 20W-20 in his car that is definitely not a beater, and posted UOAs.
Posted by: Merkava_4

Re: Advantages of straight weight oil - 03/21/14 03:18 AM

I gotta question for you guys: Why is SAE30 often labelled HD30 ?

Posted by: Shannow

Re: Advantages of straight weight oil - 03/21/14 05:26 AM

Originally Posted By: fdcg27
Even the straight grades aren't really straight.
The basestock will have its own VI, so even a straight grade will be thinner at cold start than it's SAE viscosity grade might lead you to think.
In your climate, you could probably run a 20W-20 winters and a 30 in summers with no ill effects in most engines.


To be a "straight" weight, the lubricant has to be "Newtonian", and typically/always devoid of polymeric thickeners.

So, regardless of VI, a "straight" weight will have an identical viscosity regardless of shear rate for a given temperature...if your crankshaft is spinning 1,000 RPM, 3,000 RPM, or 20,000 RPM, at 100C, your 11cst 30 will be 11cst at every rpm increment.

Until multigrades were developed, the concept of "HTHS" was irrelevant (more so "not yet needed"), the normal viscosity classifications applied, and worked everywhere.

Multigrades with polymeric VII are non newtonian, and have different viscosities at the same temperature depending on the shear rate of the oil...the viscosity in your bearing at 1,000, 3,000, or 20,000 will be different.

That's why they introduced the HTHS concept, and requirement into J300...in the words of SAE
Quote:
To insure that polymer-containing oils do not create a situation in which the viscosity of the oil decreases to less than a specified limit, minimum values of HTHS viscosity are assigned to each of the non-W viscosity grades in Table 1. A
special situation exists regarding the SAE 40 grade. Historically, SAE 0W-40, 5W-40, and 10W-40 oils have been used
primarily in light-duty engines. These multigrade SAE 40 oils must meet a minimum HTHS viscosity limit of 3.5 mPa·s.
In contrast, SAE 15W-40, 20W-40, 25W-40, and 40 oils have typically been used in heavy-duty engines. The manufacturers of such engines have required HTHS viscosity limits consistent with good engine durability in high-load, severe service applications. Thus, SAE 15W-40, 20W-40, 25W-40, and single-grade 40 oils must meet a minimum HTHS viscosity limit of 3.7 mPa·s.


http://paservice.it/wp-content/uploads/2013/06/J300_201304.pdf

Out of interest, an SAE30 "newtonian" oil of around 10-11cst, KV100 typically will be around the 3.5-4cst at 150C...the original 2.9 for the 0, 5, and 10W-40s show how badly VII wasn't so good when developed...the current requirement for 3.5 for those same grades shows just how much modern VII have improved in recent years, in being able to meet those specs in (allegedly) every oil that you see holding the SAE ratings.

A High VI "straight weight", like Amsoil 30 can claim 10W, as it's cold temperature performance can meet those requirements...but it's still newtonian and can claim "straight"
Posted by: Oil Changer

Re: Advantages of straight weight oil - 03/21/14 05:54 AM

Congratulations! You just graduated BITOG academy.

Originally Posted By: turtlevette
I think I see a pattern here. You have different "fan clubs" here. Thick oil, thin oil, and no/low VIIs. There's really no changing of anyone's mind that's going to happen.
Posted by: CourierDriver

Re: Advantages of straight weight oil - 03/21/14 06:00 AM

aaaaaaaaaaaaaaaaaamen
Posted by: Zaedock

Re: Advantages of straight weight oil - 03/21/14 09:14 AM

I found this cold viscosity info in my old files when some of us were messing with the Delo SAE30. I can't remember who calculated the numbers. It may have been Audijunkie.

Delo SAE 30
100c 12.1cST
40c 105 cSt
10c(50f): 726.5 cSt
5c(41f): 1102.3
0c(32f): 1731
-5c(23f): 2825.4
-10c(14f): 4809.1
-15c(5f): 8575.7
-20c(-4f): 16100.7
Posted by: Zaedock

Re: Advantages of straight weight oil - 03/21/14 09:23 AM

This is a cool video. I made a similar pump to transfer used motor oil. It can fill a 55 gal drum in a couple of minutes.

Keep in mind WVO is quite viscous.

http://www.youtube.com/watch?v=8o52BYTEau4
Posted by: Paul3637

Re: Advantages of straight weight oil - 03/21/14 09:28 AM

Why waste this space.

The owners manual to my el cheapo YardMarchine non-self propelled mower says to use 5W30 synthetic for all temperature ranges. Why would anyone in this century bring up single weight oil. It is not for use in any passenger car made in the last 30 years.
Posted by: Zaedock

Re: Advantages of straight weight oil - 03/21/14 09:31 AM

It's a discussion forum.

Why waste space with useless posts?
Posted by: jrustles

Re: Advantages of straight weight oil - 03/21/14 11:04 AM

Originally Posted By: Shannow
Originally Posted By: fdcg27
Even the straight grades aren't really straight.
The basestock will have its own VI, so even a straight grade will be thinner at cold start than it's SAE viscosity grade might lead you to think.
In your climate, you could probably run a 20W-20 winters and a 30 in summers with no ill effects in most engines.


To be a "straight" weight, the lubricant has to be "Newtonian", and typically/always devoid of polymeric thickeners.

So, regardless of VI, a "straight" weight will have an identical viscosity regardless of shear rate for a given temperature...if your crankshaft is spinning 1,000 RPM, 3,000 RPM, or 20,000 RPM, at 100C, your 11cst 30 will be 11cst at every rpm increment.

Until multigrades were developed, the concept of "HTHS" was irrelevant (more so "not yet needed"), the normal viscosity classifications applied, and worked everywhere.

Multigrades with polymeric VII are non newtonian, and have different viscosities at the same temperature depending on the shear rate of the oil...the viscosity in your bearing at 1,000, 3,000, or 20,000 will be different.

That's why they introduced the HTHS concept, and requirement into J300...in the words of SAE
Quote:
To insure that polymer-containing oils do not create a situation in which the viscosity of the oil decreases to less than a specified limit, minimum values of HTHS viscosity are assigned to each of the non-W viscosity grades in Table 1. A
special situation exists regarding the SAE 40 grade. Historically, SAE 0W-40, 5W-40, and 10W-40 oils have been used
primarily in light-duty engines. These multigrade SAE 40 oils must meet a minimum HTHS viscosity limit of 3.5 mPa·s.
In contrast, SAE 15W-40, 20W-40, 25W-40, and 40 oils have typically been used in heavy-duty engines. The manufacturers of such engines have required HTHS viscosity limits consistent with good engine durability in high-load, severe service applications. Thus, SAE 15W-40, 20W-40, 25W-40, and single-grade 40 oils must meet a minimum HTHS viscosity limit of 3.7 mPa·s.


http://paservice.it/wp-content/uploads/2013/06/J300_201304.pdf

Out of interest, an SAE30 "newtonian" oil of around 10-11cst, KV100 typically will be around the 3.5-4cst at 150C...the original 2.9 for the 0, 5, and 10W-40s show how badly VII wasn't so good when developed...the current requirement for 3.5 for those same grades shows just how much modern VII have improved in recent years, in being able to meet those specs in (allegedly) every oil that you see holding the SAE ratings.

A High VI "straight weight", like Amsoil 30 can claim 10W, as it's cold temperature performance can meet those requirements...but it's still newtonian and can claim "straight"


Very well stated. Thank you thumbsup
Posted by: A_Harman

Re: Advantages of straight weight oil - 03/21/14 11:53 AM

Originally Posted By: Merkava_4
I gotta question for you guys: Why is SAE30 often labelled HD30 ?



HD30: High Detergency SAE 30 weight
In contrast with ND30, which is non-detergent.
There used to be a debate 40-50 years ago about detergent versus non-detergent oils. Some would say high detergent oils would not provide good wear protection, so ran non-detergent oils in their engines, and changed oil on short intervals to keep them from sludging.
Posted by: AP9

Re: Advantages of straight weight oil - 03/21/14 12:06 PM

Originally Posted By: Paul3637
Why waste this space.

The owners manual to my el cheapo YardMarchine non-self propelled mower says to use 5W30 synthetic for all temperature ranges. Why would anyone in this century bring up single weight oil. It is not for use in any passenger car made in the last 30 years.


I understand your point, but just because not many people use straight weight in motor vehicles anymore doesn't mean it's a useless discussion, not by any means. Some of us are here to learn, not just to accept things for what they are, and that's the spirit of this forum. For example, Shannow has provided some excellent information on this thread, specifically regarding the use of VIIs and viscosities changing under different shear on the oil.

Just my 2 cents.
Posted by: edhackett

Re: Advantages of straight weight oil - 03/21/14 12:15 PM

Originally Posted By: Paul3637
Why waste this space.

The owners manual to my el cheapo YardMarchine non-self propelled mower says to use 5W30 synthetic for all temperature ranges. Why would anyone in this century bring up single weight oil. It is not for use in any passenger car made in the last 30 years.


You obviously haven't read a Subaru owner's manual up until the introduction of the FB engine a couple of years ago. My 2008 specifically allows SAE 30 and SAE 40 for desert areas or heavy duty use.

Ed
Posted by: CourierDriver

Re: Advantages of straight weight oil - 03/21/14 03:41 PM

I may try the straight 30 wgt this summer on my 3800. Have not run straight oil since the late 60s.
Posted by: Clevy

Re: Advantages of straight weight oil - 03/21/14 04:46 PM

I've used amsoils straight 60 v-twin oil in my Harley and I liked it,other than cost. I'm going to use up what I've got left once summer hits.
Posted by: Merkava_4

Re: Advantages of straight weight oil - 03/21/14 04:54 PM

Originally Posted By: A_Harman
HD30: High Detergency SAE 30 weight
In contrast with ND30, which is non-detergent.
There used to be a debate 40-50 years ago about detergent versus non-detergent oils. Some would say high detergent oils would not provide good wear protection, so ran non-detergent oils in their engines, and changed oil on short intervals to keep them from sludging.


Thanks for answering my question. I thought HD meant Heavy Duty.

Does the HD30 have more detergents than 10W-30 ?
Posted by: Red91

Re: Advantages of straight weight oil - 03/21/14 07:03 PM

This is actually a very interesting topic. My local Napa carries Delo SAE30 in quart bottles.....might try some in the GMC next oil change.
Posted by: Shannow

Re: Advantages of straight weight oil - 03/21/14 09:38 PM

Originally Posted By: Clevy
I've used amsoils straight 60 v-twin oil in my Harley and I liked it,other than cost. I'm going to use up what I've got left once summer hits.


Subject for another thread, but I don't think it's actually a straight weight.
Posted by: chainblu

Re: Advantages of straight weight oil - 03/21/14 10:25 PM

Originally Posted By: Merkava_4

I thought HD meant Heavy Duty.

I do too. I'm actually looking at a bottle of ST HD-30 that I bought yesterday for my lawn mower. It says "Heavy Duty" at the top of the label and then "Heavy Duty Formulation" lower down. Nowhere on the bottle does it say "High Detergent", but I'm sure compared to a ND-30, it IS a high detergent oil.
Posted by: Doug Hillary

Re: Advantages of straight weight oil - 03/21/14 11:46 PM

Hi,
A_Harman - It is my understanding that HD means Heavy Duty. This was most certainly the case in Europe and Oceania in the 1950s-1960 and under the nomenclature used then by the API

There were variations of this Under the Mil and CAT requirements of the time. In those years Mobil, Castrol, Shell and Caltex-Chevron made lubricants for petrol engines that had similar "detergency" levels to some Heavy Duty lubricants

That said, I used Heavy Duty lubricants in many petrol engines (both mono and multigrade) and in fact Heavy Duty lubricants were specified by VW, Porsche and Mercedes Benz in that era. And I can confirm that many of their Engineers of the era also understood that HD meant Heavy Duty

I still use HDEOs in some petrol engines too
Posted by: Now

Re: Advantages of straight weight oil - 03/22/14 03:48 AM

Originally Posted By: Clevy
I've used amsoils straight 60 v-twin oil in my Harley and I liked it,other than cost. I'm going to use up what I've got left once summer hits.


I bought about 8 quarts of SAE60 back in 1981. Bought a used 1976 FLH 1200 with 2800 miles and sold it 6 months later. Bike was not dependable to say it nicely.

I use full synthetic in all of my gas burners. I try to go way past the recommended factory interval. I've got 3 diesels that get delo 15w40. Somewhere years ago I read that straight weight oil is less likely to shear under adverse conditions. My Hondas (yes I like Hondas) are always driven between 10 and 30 miles due to our rural location.

Lots of good answers here. I know a lot about engines and oil, but for now I'm going to play dumb. I've got to allow my urine to build up for a week. I can't compete with some of these members. In case you didn't notice, there's a contest going on in this forum. LOL grin
Posted by: Ducked

Re: Advantages of straight weight oil - 03/22/14 06:42 AM

Still quite popular in Taiwan, though now a bit harder to find on supermarket shelves. My 2nd hand Ford 2L DOHC Sierra came with 5 litres of Delvac straight 40, courtesy of the previous (Taiwanese) owner. Hydraulic tappets [US: "lifters" I think] too.
Posted by: KCJeep

Re: Advantages of straight weight oil - 03/22/14 10:39 AM

Interesting thread. The UOA link posted was interesting as well. Kind of makes you wonder about all the "flow at start up" and "wear at start up" theories doesn't it?

I'll have to pay more attention but I "think" some HD30's tend to be non detergent whereas most SAE30's mirror there multi-weight counterparts in add pack but are straight weights. Not sure on that I'll have to look harder next time I am in the oil aisle.

I do know I ran SAE30 without issue in our 87 Chevy years ago without apparent issue. I didn't know a thing about oil then but it had consumption with 5w30/10w30's. I tried the straight 30 in it and zero consumption. I didn't know anything about oil back then but now you've got me wondering what a summer run of straight 30 would look like UOA wise in my Jeep! Blasted BITOG anyway ha ha.
Posted by: jrustles

Re: Advantages of straight weight oil - 03/22/14 10:58 AM

Originally Posted By: KCJeep
Interesting thread. The UOA link posted was interesting as well. Kind of makes you wonder about all the "flow at start up" and "wear at start up" theories doesn't it?


This is your last chance. After this, there is no turning back. You take the blue pill – the story ends, you wake up in your bed and believe whatever you want to believe. You take the red pill – you stay in Wonderland, and I show you how deep the rabbit hole goes. Remember, all I'm offering is the truth – nothing more.
Posted by: Zaedock

Re: Advantages of straight weight oil - 03/22/14 11:57 AM


Originally Posted By: KCJeep
Interesting thread. The UOA link posted was interesting as well. Kind of makes you wonder about all the "flow at start up" and "wear at start up" theories doesn't it?

I'll have to pay more attention but I "think" some HD30's tend to be non detergent whereas most SAE30's mirror there multi-weight counterparts in add pack but are straight weights. Not sure on that I'll have to look harder next time I am in the oil aisle.

I do know I ran SAE30 without issue in our 87 Chevy years ago without apparent issue. I didn't know a thing about oil then but it had consumption with 5w30/10w30's. I tried the straight 30 in it and zero consumption. I didn't know anything about oil back then but now you've got me wondering what a summer run of straight 30 would look like UOA wise in my Jeep! Blasted BITOG anyway ha ha.



I have a 5 or 6 year old UOA from my trail Jeep that was very good running the Delo SAE30. If memory serves, I ran about 1500 street miles (back when it was still street legal) and many gallons of fuel burned off road. My Fe number was 9 PPM. Actually, I believe sodium was elevated in that UOA as well, but potassium was 0 and we determined it was the salt treated dirt roads we were using. The 2nd and 3rd UOA's confirmed.

There are many factors that contribute to start up wear. Acid build up, condensation, cold internal components, etc. If the oil is pump-able, then typically adequate lubrication is provided. Obviously this is only to a point if it's flippn' cold out.

Originally Posted By: turtlevette
Unless the oil is in its viscosity sweet spot its in its "plastic" state and does not lubricate as well.

Also, do you think oil in a syrup like state is going to sling properly to lubricate the piston and rings?

Hello?


Turtlevette's concerns do have validity. I have seen an old white paper where they tested multi-weights against straight cold start wear(5&10W30 vs SAE30) and the straight weight actually showed slightly less wear, but I can't remember the temperature of the test. I'm sure a modern test of a 5W30 vs a SAE30 consistently tested below freezing would show less wear with the multigrade. Whether or not the wear accounts to a decrease in the useful life of the engine is another matter.

In my personal use, I have used SAE30 below freezing and watched instant flow from the rockers (BuickGN did a similar "test" watching his Grand National with 20W50). I don't remember any weird noises and the UOA looked good (not that UOA's are a wear indicator, but we still use them as such). The issue I have noticed is the parasitic loss of having to pump SAE30 or even 10W40 vs the Grp III 5W30 oil I have settled on using in this vehicle. My last UOA was very good Fe wise, so why would I not take advantage of the better flow characteristics?
Posted by: KCJeep

Re: Advantages of straight weight oil - 03/22/14 12:39 PM

Originally Posted By: Shannow

Out of interest, an SAE30 "newtonian" oil of around 10-11cst, KV100 typically will be around the 3.5-4cst at 150C...


Did I understand that right? Are you saying for example PYB SAE30 with a kv100 of 10.5 (like it's 5w/10w30 grade siblings) actually has an HTHS of about 3.5 instead of 3.0 or 3.1 for the others? That is very interesting information I had no idea.
Posted by: Red91

Re: Advantages of straight weight oil - 03/22/14 01:32 PM

Since you can still find SAE30, I don't see any reason not to use it if your application tolerates it. It's always nice to have alternatives.
Posted by: jrustles

Re: Advantages of straight weight oil - 03/22/14 02:02 PM

Originally Posted By: Zaedock
This is a cool video. I made a similar pump to transfer used motor oil. It can fill a 55 gal drum in a couple of minutes.

Keep in mind WVO is quite viscous.

http://www.youtube.com/watch?v=8o52BYTEau4


That is a awesome video, those gear style pumps are no joke thumbsup
Posted by: Shannow

Re: Advantages of straight weight oil - 03/22/14 06:20 PM

Originally Posted By: KCJeep
Did I understand that right? Are you saying for example PYB SAE30 with a kv100 of 10.5 (like it's 5w/10w30 grade siblings) actually has an HTHS of about 3.5 instead of 3.0 or 3.1 for the others? That is very interesting information I had no idea.


Yep, got only a couple minutes at the moment, but if you read the paper in the technical section on cylinder wall hydrocarbon emissions, there's a bit in the middle on temporary shear.

http://www.savantlab.com/images/TBS_Paper_-_SAE_2008-01-1621_The_Expanding_Dimensions....pdf

is a good read.

But in short, look up PDS' for straight weights, even lowly mineral oils like

http://products.lelubricants.com/Asset/8420-8450.pdf

And you can see that all this bunk about "20s that are really 30s", and "30s that are really 40s" is just waffle.
Posted by: beanoil

Re: Advantages of straight weight oil - 03/22/14 09:03 PM

I got in on the Delo buy at AZ too. I'm down to my last 5 gallons. I've run it in a 95 Chevy half ton 350, a 99 F250 5.4 Triton, a 2k Focus, my 03 6.0 Powerstroke, and Honda powered pressure washer, Briggs powered push mower, and my Kohler powered L&G tractor. There is a member here that has run a blend of 30 and 40 weight straight weight in his motorcycle with very good UOA results. There is nothing wrong with straight weights until the weather turns bitter cold. Multigrades are better then.
Posted by: Red91

Re: Advantages of straight weight oil - 03/22/14 09:11 PM

So the straight 30 did alright in your 5.4?
Posted by: jrustles

Re: Advantages of straight weight oil - 03/22/14 09:22 PM

I gotta set some time aside, just sit down and open up that technical paper forum. So much to go over in that forum, thanks to yourself and the other upstanding members.

Originally Posted By: Shannow
Originally Posted By: KCJeep
Did I understand that right? Are you saying for example PYB SAE30 with a kv100 of 10.5 (like it's 5w/10w30 grade siblings) actually has an HTHS of about 3.5 instead of 3.0 or 3.1 for the others? That is very interesting information I had no idea.


Yep, got only a couple minutes at the moment, but if you read the paper in the technical section on cylinder wall hydrocarbon emissions, there's a bit in the middle on temporary shear.

http://www.savantlab.com/images/TBS_Paper_-_SAE_2008-01-1621_The_Expanding_Dimensions....pdf

is a good read.

But in short, look up PDS' for straight weights, even lowly mineral oils like

http://products.lelubricants.com/Asset/8420-8450.pdf

And you can see that all this bunk about "20s that are really 30s", and "30s that are really 40s" is just waffle.
Posted by: KCJeep

Re: Advantages of straight weight oil - 03/22/14 09:31 PM

Thanks Shannow!
Posted by: Shannow

Re: Advantages of straight weight oil - 03/23/14 03:18 AM

I'm learning heaps being around here, and loving it.

My formal teaching was back in the late '80s, from some really clued up guys, one memorable bloke in IC engines pointed out that engines really needed three oils, one for bearings, one for pistons, and one for cams...unfortunately such an idea would never wash.

It's all about compromise in design and intent, and the more you can find out, the better decision you can make (however, a follow the manual is pretty close to the mark)

With the 'net available, there's no reason not to learn something new every day...I lay in the bath yesterday (hope it's not TMI) with a cup of coffee, and read that 2008-01-1621 paper over and over...saved it a week to get the time to absorb it (and the mineral bath salts). Those docs can give you a good bite sized understanding of another nuance in the game.
Posted by: Merkava_4

Re: Advantages of straight weight oil - 03/23/14 03:57 AM

Originally Posted By: CourierDriver
I may try the straight 30 wgt this summer on my 3800. Have not run straight oil since the late 60s.


In my Buick owners manual, it says 30 weight is OK if 10W-30 is not available, but to switch back to 10W-30 as soon as possible. I'm thinking it would only be critical in cold weather below 40* F.
Posted by: KCJeep

Re: Advantages of straight weight oil - 03/23/14 03:04 PM

I am visualizing July weather and straight 30 PYB in my sump. Hmmm.....
Posted by: A_Harman

Re: Advantages of straight weight oil - 03/23/14 03:13 PM

If we keep adding to this thread, we'll all go old school and run straight 30 in the summer, then switch to straight 10W in the winter. When was the last time anybody saw a straight W-grade on the shelf?
Posted by: Red91

Re: Advantages of straight weight oil - 03/23/14 03:16 PM

My local NAPA has 30HD PYB, GTX, Delo, and Napa. Of course it is independent and is sort of auto/farm oriented.
Posted by: beanoil

Re: Advantages of straight weight oil - 03/23/14 04:25 PM

Originally Posted By: Red91
So the straight 30 did alright in your 5.4?

IMO, yes. No difference in starting or running. But I did not do a UOA, and my tow vehicles are just that, they tow. When they aren't hooked to the travel trailer, they sit. I drive about 3000 miles a year, from March to October, then it sets all winter. So I cannot tell you if the 30 weight would have worked at or below freezing. But 40 and above, no change in the truck's behavior.
Posted by: Clevy

Re: Advantages of straight weight oil - 03/23/14 04:43 PM

Originally Posted By: beanoil
Originally Posted By: Red91
So the straight 30 did alright in your 5.4?

IMO, yes. No difference in starting or running. But I did not do a UOA, and my tow vehicles are just that, they tow. When they aren't hooked to the travel trailer, they sit. I drive about 3000 miles a year, from March to October, then it sets all winter. So I cannot tell you if the 30 weight would have worked at or below freezing. But 40 and above, no change in the truck's behavior.


That sounds like ideal conditions for using a straight grade.


And thanks for the links Shannow. You are certainly an asset to this forum and us less informed members.
Posted by: Garak

Re: Advantages of straight weight oil - 03/23/14 04:51 PM

Originally Posted By: A_Harman
When was the last time anybody saw a straight W-grade on the shelf?

I don't even see any on my Imperial Oil sell sheets. Heck, they don't even sell a Mobil conventional 10w-40 or 20w-50 up here any longer, and all their monogrades are SAE 30 and SAE 40 HDEOs and two cycle diesel oils.
Posted by: Red91

Re: Advantages of straight weight oil - 03/23/14 06:05 PM

Would anyone here actually try a fill of monograde in an application where it's tolerated? Just for kicks.
Posted by: Clevy

Re: Advantages of straight weight oil - 03/23/14 06:11 PM

Originally Posted By: Red91
Would anyone here actually try a fill of monograde in an application where it's tolerated? Just for kicks.


I'm considering trying a 30 grade in my charger,just for xxxx and giggles.
Posted by: Red91

Re: Advantages of straight weight oil - 03/23/14 06:29 PM

What engine do you have in the charger?
Posted by: KCJeep

Re: Advantages of straight weight oil - 03/23/14 08:50 PM

Originally Posted By: Red91
Would anyone here actually try a fill of monograde in an application where it's tolerated? Just for kicks.


I imagine my tractor engine Jeep would thrive on it. Seriously considering it for fun but I have some timing problems. I'd only consider it during summer and for any kind of telling results it would be better for it to be a second run UOA to get a real look at how it did. If I was due for an OCI now it would work, but I'm not. frown

Another reason why I don't usually run synthetics, you just have to wait to darn long to try something new!
Posted by: gfh77665

Re: Advantages of straight weight oil - 03/23/14 08:56 PM

Originally Posted By: Red91
Would anyone here actually try a fill of monograde in an application where it's tolerated? Just for kicks.


I have posted the following twice:

I have:

1) Mixed 30 with 10-30 in varying amounts
2) Ran straight 30
3) Even ran straight 40 (Im in TX summer and oil was almost free)



Even the 40 did fine in my 97 Chevy pickup.

People are STRESSING over nothing, viscosity wise.
Posted by: turtlevette

Re: Advantages of straight weight oil - 03/23/14 08:57 PM

Originally Posted By: Clevy
Originally Posted By: Red91
Would anyone here actually try a fill of monograde in an application where it's tolerated? Just for kicks.


I'm considering trying a 30 grade in my charger,just for xxxx and giggles.


I'm going to put 0W-16 when it comes out, in my corvette for the same reason.
Posted by: Clevy

Re: Advantages of straight weight oil - 03/24/14 01:42 AM

Originally Posted By: Red91
What engine do you have in the charger?


5.7 litre hemi. With mds. I've already experimented with 40 grade oils in it and they slow down mds engagement by .025 of a second or so,so those folks who believe that you gotta run a 20 grade or the mds won't work take note that it's not true.

Surprisingly enough if you get on the throttle before the oil reaches 140f the ecu throws an oil too thick code.
I've got 5w-20 ultra in it right now. 8000 miles on the oil and I guess due to oxidative thickening it set a cel a few days ago when I got heavy into the pedal.
Posted by: Shannow

Re: Advantages of straight weight oil - 03/24/14 04:51 AM

Originally Posted By: A_Harman
If we keep adding to this thread, we'll all go old school and run straight 30 in the summer, then switch to straight 10W in the winter. When was the last time anybody saw a straight W-grade on the shelf?


I've seen a 20W...somewhere in the not too distant past, now I'm wracking my brain for where exactly I saw it...it stood out
Posted by: Red91

Re: Advantages of straight weight oil - 03/25/14 07:34 AM

So you think it would be alright in the summer on a monograde? I'm seriously very curious.
Posted by: KCJeep

Re: Advantages of straight weight oil - 03/25/14 10:16 AM

Originally Posted By: Red91
So you think it would be alright in the summer on a monograde? I'm seriously very curious.


I do because I've done it before many years ago but I was very oil ignorant then and ran it into winter. Starts were pretty rough ha ha. I've been looking around and PYB HD30 is fairly available. So is Rotella. I also looked at the Castrol site and they say in regard to their HD 30 "for ambient temps over 40 degrees". So they seem to think HD30 is fine as long as it's 40 or above.

I am still 3-4k away from my next OCI, it will be summer then, I am torn between another fill of 10w40 PYB or a run of HD30 PYB. But I would rather have a prior run of PYB before I run the HD30 as a UOA would be more reflective of actual performance. But then I'd be getting into fall with HD30 which I don't really want to do. But a single run would not be worthless either.

Like you I am very intrigued by the higher HTHS and the stellar shear resistance.
Posted by: dlundblad

Re: Advantages of straight weight oil - 03/25/14 10:24 AM

In the summer heat at least, I wonder if it would be beneficial to buy PYB HD 30 weight to use as that 6th quart or as a top off oil.

Didnt AZ have some on clearance for $5 per 5 qt jug??
Posted by: Red91

Re: Advantages of straight weight oil - 03/25/14 05:47 PM

I'm looking at Delo SAE30 from my local NAPA. I'd be running it in a '91 GMC Sierra with a TBI 5.7. Probably all seasons due to the fact that it's a second vehicle/beater, and it will probably not even see 500 miles a year any longer. I'm sticking with 5W-30 in the Dakota.
Posted by: friendly_jacek

Re: Advantages of straight weight oil - 03/26/14 12:24 AM

When a boating store went out of business several years ago, they had a huge clearance on marine 15W40 and 40 oils (under a buck per qt). They look like repackaged HDEO. Not being sure which is better for my boat, I typically blend them and this comes closer to the 25W40 Mercruiser specifies for the engine, LOL.

However, one time I used straight 40 only and it was a pain to drain the cold oil during late fall. The oil was ridiculously thick in ambient temps.
Posted by: Shannow

Re: Advantages of straight weight oil - 03/26/14 03:32 AM

Originally Posted By: dlundblad
In the summer heat at least, I wonder if it would be beneficial to buy PYB HD 30 weight to use as that 6th quart or as a top off oil.

Didnt AZ have some on clearance for $5 per 5 qt jug??


PYB SAE30 used to be available down here, and had become a significant part of my normal purchasing, using it in my BJ42, and J-Car wagon (before I used 25W-70 in it one winter to demonstrate that it wouldn't blow it up). The PYB had up to date "S" specs.

Alas, the only generally SAE30s that are typically available are Delvac 1330, which I tend not to use (would be all over 1630), and various lawnmower oils, which I resorted to with my E30, running a fill of Caltex mower oil (Delo 500 at the time).

Note, that in every case, the 30 was thinner at 100C than the recommended for my vehicle in the manual...but was relying on hths, not KV100.
Posted by: supercity

Re: Advantages of straight weight oil - 03/26/14 07:01 AM

Originally Posted By: Shannow



Alas, the only generally SAE30s that are typically available are Delvac 1330, which I tend not to use (would be all over 1630), and various lawnmower oils,


RX Mono 30 should be easy enough to get. It's sold in 5L jugs
Posted by: Ducked

Re: Advantages of straight weight oil - 03/26/14 08:05 AM

I read an article online a while ago that suggested straight weight oil offered better corrosion protection to light aircraft engines (which sit idle for long periods) because it was retained on the parts better.

Failure rates were allegedly higher with multigrades.

Since my car sits idle for long periods, that'd be a reason to use it. Its got a mixture of CPC straight 40 and Delvac 15/40 in it at the moment, but summer is just around the corner.

Can't find the article now, unfortunately.
Posted by: Zaedock

Re: Advantages of straight weight oil - 03/26/14 08:17 AM

I ran the Delo SAE30 because I bought a butt load of it for $.99/gallon. If that deal didn't exist, I wouldn't purposely go out and buy a SAE30 when 5W30 is typically the same price and offers superior performance in most cases.
Posted by: Zaedock

Re: Advantages of straight weight oil - 03/26/14 08:25 AM

Originally Posted By: Ducked
Since my car sits idle for long periods, that'd be a reason to use it.


Not really. I doubt you run an air cooled, opposed, dry sump engine that burns leaded av gas.

My vehicles sit for extended periods outside and 5W30 has more than been up to the task, especially if your interval extends into the winter months.
Posted by: Ducked

Re: Advantages of straight weight oil - 03/26/14 08:26 AM

Don't think this is it, but the content is similar

http://www.avweb.com/news/savvyaviator/savvy_aviator_52_thinking_about_oil_changes_196730-1.html
Posted by: Ducked

Re: Advantages of straight weight oil - 03/26/14 08:34 AM

I'm in Taiwan, but I have heard of these "winter months" of which you speak.

Re "5W30 has been more than up to the task" I could say straight 40 was more than up to the task in my Sierra, but you wouldn't know what, if anything, that meant, either.
Posted by: Zaedock

Re: Advantages of straight weight oil - 03/26/14 08:56 AM

While SAE40 is up to the task, there is no reason to use a lubricant that thick in your location.
Posted by: KCJeep

Re: Advantages of straight weight oil - 03/26/14 10:33 AM

Well PYB HD30 is available here at a bunch of locations, but I have yet to find a jug to keep the costs down. Napa does have it "on sale" for $3.59 a quart though I'd like to do better. Rotella SAE30 is available at Tractor Supply in jugs but I want to run PYB, it has been my favorite lube in the Jeep thus far.

I will look at Autozone.
Posted by: KCJeep

Re: Advantages of straight weight oil - 03/26/14 11:42 AM

Okay here's a related question. Why is the TBN on PYB HD30 about 7 when the TBN on PYB 5w30 is almost 10? According to Pennzoil the HD30 still has detergents and anti wear additives, it even has the "removes up to 40% of sludge on the first change" advertising stuff on it.
Posted by: Zaedock

Re: Advantages of straight weight oil - 03/26/14 01:28 PM

Not sure why TBN is lower compared to it's multi-weight counterpart.

The Delo SAE30 TBN from '05 is 10.1.
Posted by: gfh77665

Re: Advantages of straight weight oil - 03/26/14 01:31 PM

Originally Posted By: dlundblad
In the summer heat at least, I wonder if it would be beneficial to buy PYB HD 30 weight to use as that 6th quart or as a top off oil.


I have done that for years. I always felt it would combat the shearing that naturally occurs.
Posted by: KCJeep

Re: Advantages of straight weight oil - 03/26/14 04:36 PM

I am still intrigued, found an interesting thread from '09 on straight weights.

SAE 30 BITOG thread
Posted by: Red91

Re: Advantages of straight weight oil - 03/26/14 06:08 PM

I figure part of being a part of this forum is a willing to experiment. smile
Posted by: Ducked

Re: Advantages of straight weight oil - 03/26/14 09:08 PM

Originally Posted By: Zaedock
Originally Posted By: Ducked
Since my car sits idle for long periods, that'd be a reason to use it.


Not really. I doubt you run an air cooled, opposed, dry sump engine that burns leaded av gas.



True, though I'm not sure how those factors affect the analogy, if at all.

The difference in the oils is perhaps more relevant.

As I understand it (I havn't researched this and could easily be wrong) straight aviation lubricants for piston engines are typically of higher viscosity (eg Aeroshell range goes from 65 to 120) and non-(metallic)-detergent. These properties might reduce drain-down and increase corrosion protection relative to the automotive equivalents.
Posted by: KCJeep

Re: Advantages of straight weight oil - 03/26/14 09:57 PM

Originally Posted By: Red91
I figure part of being a part of this forum is a willing to experiment. smile


This place is terrible for that I can't get in all the fiddling I want to do, it's the BITOG curse. Leaning hard towards a run of PYB HD30 for curiosity's sake though.
Posted by: Zaedock

Re: Advantages of straight weight oil - 03/26/14 10:03 PM

Fiddling is cool. Having done the SAE30 thing, I'll be fartn' around with 5W20 in my Jeep 2.5L powered buggy this summer. I may do a build thread if there is interest.
Posted by: Zaedock

Re: Advantages of straight weight oil - 03/26/14 10:15 PM

Originally Posted By: Ducked
Originally Posted By: Zaedock
Originally Posted By: Ducked
Since my car sits idle for long periods, that'd be a reason to use it.


Not really. I doubt you run an air cooled, opposed, dry sump engine that burns leaded av gas.



True, though I'm not sure how those factors affect the analogy, if at all.

The difference in the oils is perhaps more relevant.

As I understand it (I havn't researched this and could easily be wrong) straight aviation lubricants for piston engines are typically of higher viscosity (eg Aeroshell range goes from 65 to 120) and non-(metallic)-detergent. These properties might reduce drain-down and increase corrosion protection relative to the automotive equivalents.


*sigh* - the analogy is that your application is completely different and not comparable to your vehicle use or the type of fuel it burns (oil is contaminated by combustion byproducts).

I have been working on engines for over 20 years. I have completed engine replacement with both rebuilt and used units. In the extreme cases, I have pulled apart engines that sat on a shelf for a decade and the inside was coated with oil. You are looking for a "protection" that is not needed. Run the recommended viscosity and enjoy your vehicle.
Posted by: Red91

Re: Advantages of straight weight oil - 03/26/14 10:29 PM

That will be a nice read. Always exciting to see what we come up with through experimentation.
Posted by: edhackett

Re: Advantages of straight weight oil - 03/26/14 10:33 PM

Originally Posted By: Ducked
hed this and could easily be wrong) straight aviation lubricants for piston engines are typically of higher viscosity (eg Aeroshell range goes from 65 to 120) and non-(metallic)-detergent. These properties might reduce drain-down and increase corrosion protection relative to the automotive equivalents.


Aviation single grade oil viscosity is on a different scale than SAE automotive oils. Divide by 2 to get the equivalent SAE viscosity. 100 = SAE 50. The multi-grades are on the SAE scale.

Ed
Posted by: Merkava_4

Re: Advantages of straight weight oil - 03/27/14 01:06 AM

Straight grade oil is the real deal. Heavy duty stuff. No artificial thickeners added.
Posted by: il_signore97

Re: Advantages of straight weight oil - 03/27/14 10:15 AM

Originally Posted By: Red91
Would anyone here actually try a fill of monograde in an application where it's tolerated? Just for kicks.


I've tried SAE30 in several vehicles just for kicks. Mind you, I should qualify that. I used Amsoil's fully synthetic ACD SAE30, which by nature of it's synthetic base stocks, can qualify for 10W30's cold temp pumpability. So essentially, it can be considered a VII-free, synthetic 10W30 oil that is properly categorized as an SAE30.

My impressions vs. the typical syn 0W30 or syn 5W30 that I've normally used prior to that in the particular vehicles in question... I noticed no difference whatsoever in driveability. Summer cold starts were identical as expected, and winter cold starts had a very very slightly slower cranking speed compared to the usual 0W30 (again, to be expected). No funny noises. Quiet and smooth engine running. Was looking to identify any wear metal changes in UOA, but I don't think it made any difference in that regard.

So in short, after many runs in different vehicles, I haven't felt the need to run it again. I'm not sure if there would have been long term benefits or detriments of using it. Even in my lawn and garden equipment I usually use 5W30 syn and call it a day (especially for the genset and snow blower that will be started in very cold weather - I'm not concerned about the lawnmower so much).
Posted by: KCJeep

Re: Advantages of straight weight oil - 03/27/14 11:44 AM

Originally Posted By: Zaedock
Fiddling is cool. Having done the SAE30 thing, I'll be fartn' around with 5W20 in my Jeep 2.5L powered buggy this summer. I may do a build thread if there is interest.


Of course there is interest!

My guess would be your iron will be relatively normal and your aluminum will skyrocket if you run a 5w20. The two Jeep UOA's with a 20 grade that I've seen exhibited that trend.
Posted by: Ducked

Re: Advantages of straight weight oil - 04/01/14 05:34 AM

Originally Posted By: edhackett
Originally Posted By: Ducked
hed this and could easily be wrong) straight aviation lubricants for piston engines are typically of higher viscosity (eg Aeroshell range goes from 65 to 120) and non-(metallic)-detergent. These properties might reduce drain-down and increase corrosion protection relative to the automotive equivalents.


Aviation single grade oil viscosity is on a different scale than SAE automotive oils. Divide by 2 to get the equivalent SAE viscosity. 100 = SAE 50. The multi-grades are on the SAE scale.

Ed


Like gear oil viscosities aren't comparable with engine oil? (Never understood why they do that, but I suppose there's no one to stop them.)

Thanks. That means the analogy is closer than I thought.

(But of course not the same, because its an analogy.)

(Sigh)
Posted by: Shannow

Re: Advantages of straight weight oil - 04/01/14 05:41 AM

The aeros are started, and then usually run for a while, not a 2 minute jaunt down to the street.

The "advantages" of high VI don't play out in that sort of application...
Posted by: Ducked

Re: Advantages of straight weight oil - 04/07/14 08:44 AM

Originally Posted By: Shannow
The aeros are started, and then usually run for a while, not a 2 minute jaunt down to the street.

The "advantages" of high VI don't play out in that sort of application...


I don't do 2 minute jaunts down the street. I have a bicycle.

(It takes straight weight oil too.)

But sure, in general, aero engines have a much less demanding role than car engines, but my original point was the alleged enhanced corrosion resistance of higher viscosity straight weight oils for (aero} engines that sit idle for long periods.

Whatever the design and operational differences, I'd have thought that sitting idle is going to be rather similar in a car and an aircraft engine.
Posted by: Ducked

Re: Advantages of straight weight oil - 04/07/14 08:53 AM

Wandering around B+Q a while ago and noticed the following:-

OE/HDO-30 Lubricating oil, Internal Combustion Engine. Combat/Tactical Service MIL-PRF-2104E

Presumably thats a straight 30 weight oil. This was in the section that displays welding sundries and such, and I'd guess generators might spec a straight 30 oil.

I quite favor straight oils here, especially in a motorcycle, but have only used 40W (which might be rather high) because thats all I've found readily available. It wasn't expensive at 400NT a gallon, though it was only a little toy American gallon, so not as cheap as I at first thought.

Its not unusual in the UK for an oil to give its milspec on the label, but thats ALL this stuff had. Otherwise plain white plastic jerrycan, no brands/logos/pretty colours. Not B+Q's normal style at all.

Apparently made (or at least sold/packaged) by Chemical Specialist and Developments, Inc, Conroe TX 77305. I wondered if it might be fake, though you'd think B+Q would buy in enough bulk that they'd check supplier bonafides. There were a few typos on the label, but not beyond the usual run of industrial illiteracy. Health and safety stuff was a bit over the top, but that's not implausible for a US company.

Company website says they are mostly a defence contractor, (which fits) and not much else apart from "mission statements" and similar [censored].

Having checked it out a bit I went back a week or so later to get some for the "not summer", but it'd gone, and (of course) no one knew what I was talking about.

On the same shelf there were tins of Nyco Grease GN10. Looked it up. Its a general purpose AVIATION grease, made by a French company, and specified for extreme low temperature use (presumably at altitude).

I have no clue as to what it was doing on the shelf in B+Q in Taiwan.

Not important, but these little mysteries intrigue me. Stuff like this is why women find me such a fascinating conversationalist.
Posted by: KCJeep

Re: Advantages of straight weight oil - 04/07/14 12:13 PM

Well I was going to do a run of SAE30 this summer. Now I've been transferred at I will suddenly be extreme short tripping my Jeep. Not thinking that's the scenario for a straight weight.

I dunno maybe it'd be better?
Posted by: pavelow

Re: Advantages of straight weight oil - 04/07/14 01:11 PM

Who uses straight weight oils in 2014? I can't see any use for them except for in lawnmowers and other small engines? lol
Posted by: kschachn

Re: Advantages of straight weight oil - 04/07/14 01:40 PM

I don't even use it for them, I see no excessive consumption on M1 0W-30 so what's the point? Why make it any harder than it needs to be?

Originally Posted By: pavelow
Who uses straight weight oils in 2014? I can't see any use for them except for in lawnmowers and other small engines? lol
Posted by: hattaresguy

Re: Advantages of straight weight oil - 04/07/14 05:08 PM

I used to use straight weights in lawn mowers but now even the little engines are all calling for 10w30.

Unless its for an old engine or an air compressor straight weights are obsolete.

A lot of the old timers run them in their boats but I don't see what advantage they offer over any of the modern 15w40's. Certainly not cost 15w40's are always cheaper.
Posted by: zamadison

Re: Advantages of straight weight oil - 04/07/14 07:00 PM

I could see a straight weight oil being best in an application where an engine was run continuously for long periods of time and not shut down and restarted very often at all.
Perhaps a generator of some sort?
Posted by: kschachn

Re: Advantages of straight weight oil - 04/07/14 08:06 PM

Meh, I have an 8kW standby generator (Briggs twin) using 0W-30, and it runs now and then when the power fails. I really don't have to add any oil between changes which is usually twice a year.
Posted by: Ducked

Re: Advantages of straight weight oil - 04/08/14 10:40 PM

Originally Posted By: zamadison
I could see a straight weight oil being best in an application where an engine was run continuously for long periods of time and not shut down and restarted very often at all.
Perhaps a generator of some sort?


I could see straight weight oils being best in an application where they never see low temperatures (due to climate or preheat), where the oil is subject to sheer (all applications, but especially motorcycles) where the alleged high startup wear (alleged because although I've seen the numbers quoted a lot, and they are plausible, I've never seen a source for them) is less of an issue due to the above, or due to the use of a prelube system, where the engine sits idle for long periods of time, or where the inferior (?) lubrication of polymeric viscosity modifiers is an issue.

Thats potentially A LOT of applications, but I don't know what the advantages (if any) are ACTUALLY, because I've seen hardly any evidence.

Either way, it's probably out there, but I havn't seen it. A lot of it is probably secret.

Someone on here recently (I thought it was in this thread, but I can't find it) posted a response along the lines of "or do you think multigrades are just a worthless marketing ploy" as if that was inconceivable.

I don't think they're just a marketing ploy, but "worthless marketing ploy" is, in a commercial context, a contradiction, like military intelligence.

If a marketing ploy is effective, it'll be anything but worthless to the people who implement it, regardless of any technical merit.