Advantages of straight weight oil

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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.
 
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.
 
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
 
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.gif
 
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.
 
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.
 
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.
 
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?
 
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.
 
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.
 
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.
 
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.
 
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.
 
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.
 
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