Why are some trying to thicken their oil?

[BrianWC]

Quote:

---

SFCP: There always seems to be a portion of the BITOG crowd that seems to firmly believe that thicker is better. Why, exactly that "old school" concept often comes up leaves me clueless. Why someone would go out and pay a small fortune for a nice normal street car that calls for a 5W-20 oil; and how that same someone who lives in maybe, Bozoville, LA where it is hot but ain't the Sahara, can convince himself that he needs a 20W-50 oil in it beats the holy logic out of me every time!

Of course, I'm exaggerating a good bit here, but the point is that I'd bet a lot of those same people here on BITOG of the ardent "thicker is better" persuasion really haven't read much, or any, of Dr. A.E. Haas epistle on the virtues of thin engine oils. A highly logical and convincing article. Even if they did read it, they probably couldn't accept the message very well. Not withstanding other points of view, I follow what my owner's manual says about oil selection as the compromise position between BITOG ideas, the vehicle's engineers, and what I "feel" is best.

---

Bozoville, is that near Ponchatoula?

One thing a lot of y'all are forgetting is that there are plenty of folk here who use thicker oil b/c they've found nothing in their grade that prevents consumption. Additionally, there are still plenty of cars like Euros that spec the thick stuff. My SAAB specs 5W30 or 5W40 but allows up to 60 weight. I'd love to use only 5W30 but given design problems with the oil pump, it seems 40 weight is the better bet. What I don't understand is why people care so much about people using thick oil. If they want to, who cares? People have been doing it for many years before AE Haas enlightening discourses. If engines can survive knuckleheads pouring whole bottles of STP in because RIchard Petty says so, I doubt a 40 weight synth is going to be a real dealbreaker.

Not saying anything is wrong with a 20 weight. If I could ever find any on sale, it'd be all my Honda would touch. But this bang you over the head attitude that everyone has that someone is an idiot if they don't use the thinnest oil possible is getting a tad old.

Of course, it goes both ways, and no one is an idiot for using 20 weight oil....

But if we let people live and let live, this would be a boring forum, wouldn't it? All we'd be able to discuss is group III Mobil1 and whether or not it cures or causes cancer, increases/decreases s-exual stamina, and feeds/kills starving people in Africa.

 

[Merkava_4]

You've got to ask yourself these two questions:

1) Will my thin oil protect my engine by keeping the crank shaft main journal from contacting its mating bearing surfaces under load?

2) Will my thick oil flow to the top of my engine and lubricate my cam followers quick enough on a cold day when I turn the key?

The trick is finding the happy medium.

 

[Mystic]

I don't understand either why so many people here seem to want to always thicken their oil even in cold weather. Thin, more freely flowing motor oil improves fuel economy and although you should not go too thin the oil that is thin that will do the job is better.

Now, to be honest 5W20 oil makes me nervous and if I had a Ford or a Honda that required it I would probably use synthetic. And if 5W30 was allowed in the summer I might use 5W30. My car uses 5W30 with 10W30 allowed in warm weather only. I use 5W30 year round although I have used 0W30 in the winntertime (it is allowed in my owner's manual). Heck, there is evidence that 5W30 is often superior motor oil to 10W30. So why use the thicker oil even in warm weather?

Now a diesel ususally requires thicker oil-maybe 15W40 or 5W40 in cold weather or 10W30. So you use the proper oil for the diesel.

There are a very few cars and trucks that require thicker oil and in a worn engine thicker oil might be better in the summer. If a car requires 15W50 oil than use it. If you have a worn engine and 10W30 slows down the oil consumption in hot weather than use it.

I don't much believe in oil supplements. If I used a supplement I would use something like Vavoline oil supplement and I would add just a few ounces of supplement and only in warm weather. I would be more likely to add a very small amount of Valvoline oil supplement to a lawnmower than a car or truck engine.

Really, the only oil supplement I use now is Auto-RX, which is an engine cleaner. I am always trying to find the best motor oil (with the help of this website) but I have pretty much given up on supplements. Now if some truly miracle product came along which everybody agreed improved fuel mileage and reduced engine wear I would use it. But the only supplements of any kind I use now are Auto-RX, Bar's Leaks, and fuel system cleaners. I still have some faith in Lubegard products but I have not used one in a long time.

It is an old concept that thicker oil protects an engine better. That is the reason STP Oil Treatment used to be sold in such huge numbers. Now, back in the STP days motor oils were not as good as today and maybe STP was not so bad to add to an engine back in those days (in warm weather). Today, I would not put STP in my lawnmower engine even if I could get the STP for free.

This old myth that thicker oils protect better will never die. Just like some people still believe in the Pennzoil sludge myth.

 

[mdocod]

the concern that the thin oil won't have enough support for the main bearing, while a thick oil won't flow well enough to the top end on a cold day, can all be solved very easily.

Use Synthetic. As I understand, Synthetic has about 7 times the film strength of dino, and we all know it flows well in the cold. I'd be willing to bet that a premium grade synthetic like amsoil 0W20, would provide better bearing protection than a 20w50 supertech.

 

[06VtecV6]

It's funny because my previous oil was DC blend and it took forever to warm up from cold start while the MC I am on now was almost twice as quick but it's supposed to be as thick, 8.8 cSt at 100 versus only 1 tenth more 8.9 for the DC blend. The FP is 185 for MC and 200 for DC so maybe that has something to do with it. Any ideas?

 

[Merkava_4]

Quote:

---

the concern that the thin oil won't have enough support for the main bearing, while a thick oil won't flow well enough to the top end on a cold day, can all be solved very easily.

Use Synthetic. As I understand, Synthetic has about 7 times the film strength of dino, and we all know it flows well in the cold. I'd be willing to bet that a premium grade synthetic like amsoil 0W20, would provide better bearing protection than a 20w50 supertech.

---

That's a very interesting statement; the mere thought of synthetic oils having 7 times the film strength of a dino of equal viscosity, is worthy of having a thread all to itself I would think.

 

[teven7492]

Quote by mdocod , synthetics have 7 times the film strength of dino . This qoute is not TRUE show me facts that back up this silly statement, ARE YOU AN AMSOIL DEALER.

 

[BrianWC]

The only oil I've seen hype that is Redline. Don't they claim their 5W20 has the film strength of a dino 10W40 or something?

 

[cfromc]

I too would like some information regarding the film strength. I seem to remember that the film strength was about the same or only slightly different, definitely not 7 times. Redline also has a much higher HTHS given a weight rating vs. others with the same rating.

 

[BOBISTHEOILGUY]

Quote:

---

Quote by mdocod , synthetics have 7 times the film strength of dino . This qoute is not TRUE show me facts that back up this silly statement, ARE YOU AN AMSOIL DEALER.

---

let me tell you some things you may not know. first, the thick oil additive your referring to, it causes your pistons to seal better if your engine is older, that will cause your mpg to increase as it causes a better seal for better combustion.

oil has come a long way from the old days that a lot of people still believe. they have been taught by the older guys that use to do mechnanics and saw how the thicker oils would protect better as it did because it had a better hydodynamic lube. now a days, they have better additives that protect the engine like the old oils did but also gives better mpg because it has less drag on the engine because the oil is thinner.

as for synth vs miners, syth lasts longer than min oil. they do ever so slightly protect as I see it, but the additives do all the work at protecting. if sysnth did all the protecting, then they dont need the additives, which of course they do. look at the uoa's and you'll see they all have additives.

you don't need thicker oil on your engine but as it gets older, it will use or loose thinner oil and you will need to thicken it up. thats what I have found using uoa's. you will see rings getting looser and will cause thinner oil to burn off, that would mean to increase your thickness of your oil. I personally would go to a straight wt oil like 40wt (unless your up north) as time goes on and you burn oil.

hope that helps.
bob

 

[cfromc]

Thank you Bob. I was afraid to say how much using VSOT helped my MPG (>5%) for fear that people would think I was full of IT. Since I changed my oil (without adding VSOT) my MPG has gone down again. Yesterday it was $102 to fill my tank, guess I will be using some VSOT again. I will continue to monitor the MPG. Unfortunately, it seems like the MPG does slowly return to "normal" again a few thousand miles after putting the VSOT in. Should I just move up a grade of oil? I have 130K on the engine and am looking at either an HDEO 5W-30 or a PMCO 10W-30, now perhaps even a 5/10W-40.

 

[TallPaul]

The remarkable thing about VSOT is that while it will thicken your oil a couple cSt, it can improve fuel mileage (per cfromc, above), and it is supposed to improve cold starts. Wonder what miracle ingredient is in it. Maybe its base is a very thick PAO?

As for thickening oil. Think about the typical 30 weight oil is around 10.5 cSt and the typical 40 weight is around 14 cSt. Seems rather odd to jump from one to the other, when maybe your engine needs something in between. Mixing same brand between two grades seems a no-brainer solution to get the exact viscosity you want (and hopefully the engine wants/needs).

 

[1999nick]

Quote:

---

The only oil I've seen hype that is Redline. Don't they claim their 5W20 has the film strength of a dino 10W40 or something?

---

Reminds me of Mobil One when it first came out back in the 70's. It was first marketed as a 5W20, and they said it was the equivalent of 10W40 mineral oil.

 

[Rickey]

Quote:

---

Thank you Bob. I was afraid to say how much using VSOT helped my MPG (>5%) for fear that people would think I was full of IT. Since I changed my oil (without adding VSOT) my MPG has gone down again. Yesterday it was $102 to fill my tank, guess I will be using some VSOT again. I will continue to monitor the MPG. Unfortunately, it seems like the MPG does slowly return to "normal" again a few thousand miles after putting the VSOT in. Should I just move up a grade of oil? I have 130K on the engine and am looking at either an HDEO 5W-30 or a PMCO 10W-30, now perhaps even a 5/10W-40.

---

My 2 cents worth: I would guess that your oil/additive combination is shearing down in viscosity. Therefore the MPG loss after some mileage.
My suggestion would be a 5w40 such as Rotella T synthetic or one of the "european" oils and just skip the additive.
Not to bash VSOT mind you, I use the stuff in small doses in all my vehicles.

Rickey

 

[Rickey]

Lets consider this:
Isn't it rather curious how a "thick" oil can be used to compensate for engine wear after years of "thin" oil useage.
And on the other hand a "thin" oil is never used to compensate for engine wear after years of "thick" oil useage.
Anyone...please show me an example that proves this statement incorrect.

Rickey

 

[Truck&Cycle]

Because they wised up and realized that manufactures want thin oil to meet EPA mandates on the entire fleet and only have to worry about the vehicle until the warranty is up.

They figured out how thin they could go to get a tolerable percentages of engines past the warranty mileage and that is what they will recommend.

 

[Steve S]

Quote:

---

the concern that the thin oil won't have enough support for the main bearing, while a thick oil won't flow well enough to the top end on a cold day, can all be solved very easily.

Use Synthetic. As I understand, Synthetic has about 7 times the film strength of dino, and we all know it flows well in the cold. I'd be willing to bet that a premium grade synthetic like amsoil 0W20, would provide better bearing protection than a 20w50 supertech.

---

paos film strength is hardly better than petro oil ,the esters are better film strength wise.

 

[TallPaul]

Redline 5w20 has the HTHS of a good 10w30 conventional oil. I would guess the HTHS is fairly well correlated with film strength.

 

[Gary Allan]

Quote:

---

Because they wised up and realized that manufactures want thin oil to meet EPA mandates on the entire fleet and only have to worry about the vehicle until the warranty is up.

They figured out how thin they could go to get a tolerable percentages of engines past the warranty mileage and that is what they will recommend.

---

You have to keep in mind, Truck&Cycle, that there are millions of units, many still on the road today, that have been running thinner than spec'd oils if they went over a couple of thousand miles on a oil change. Although they've appeared to have improved in shear stability, most 5w-30 were reduced to 20 weights in use. This evolution to starting out with 20 weight oils just required some R&D and the will to make them marketable.

 

[cfromc]

Quote:

---

As for thickening oil. Think about the typical 30 weight oil is around 10.5 cSt and the typical 40 weight is around 14 cSt. Seems rather odd to jump from one to the other, when maybe your engine needs something in between. Mixing same brand between two grades seems a no-brainer solution to get the exact viscosity you want (and hopefully the engine wants/needs).

---

TallPaul, some companies, like Redline state that it is completely fine to mix their products, others, like Amsoil, state that it is not fine and will produce an inferior product than either of the original products by themselves. I have asked for opinions on this in the past and gotten mixed responses. I do tend to make changes like this in incremental steps. For example, I wanted a thicker oil for my motorcycle so I used half Redline 20W-50 and half 20W-60. I like the change so far so I will go further and use all 20W-60 next season. For my truck I was looking at a thick 30-weight oil to see if it helped the engine noise and MPG. If that works, maybe a thin 40-weight next OCI. Or, if I decide to use Redline, I may mix but with the Redline, it already runs a little on the thick side so just using mostly 5W-30 should show a change if there is a benefit to be had from going thicker.