Does Thin Oil really Lubricate better?

[HangerHarley]

If so, then why do some engines thrive on 10W-40 and maybe even 20W-50? Some even spec 5W-50 while most German cars like 0W-40. And while GC is a 0W-30, there are still applications for, say a 0W-40 or 5W-40 that make me have to ask.. Thin Oil?

Basically, GC is a 0w30 so it SEEMS Thin. However i wonder the highest application people have substituted its Viscosity for.

For example, do people use GC 0w30 where a 0W-40 or 10W-40 would normally be first choice?

And does Thin Oil lubricate better, all the time?

 

[aquariuscsm]

I say no way! Or to better put it,I should say it depends on the type of engine,and the application the engine is used.

 

[HangerHarley]

Originally Posted By: aquariuscsm
I say no way! Or to better put it,I should say it depends on the type of engine,and the application the engine is used.


Yeah. Maybe i worded it poorly, but this thread i meant to ask "What applications thrive on thin oil, or Engine Designs" and "Which like thicker stuff."

GC seems to combine both worlds, so i wonder how thick people go with it. And if it is wise to use Thick 0w30 even GC in apps calling for 5W-40 and such.

 

[d00df00d]

Thin oil generates less drag, flows faster, and cools better. Thick oil generates thicker films and higher oil pressures. Which one you want depends on the design of the engine, how it's going to be used, etc. It's a pretty complicated issue.

One correction, by the way: 0w and 5w do NOT indicate "thick" or "thin" oils. They are cold pumpability ratings, which are different from kinematic viscosity ratings like the 30/40/50 in the examples you gave. A 0w-40 is closer to a 10w-40 than it is to a 0w-30.

 

[BobFout]

Originally Posted By: HangerHarley
Originally Posted By: aquariuscsm
I say no way! Or to better put it,I should say it depends on the type of engine,and the application the engine is used.


Yeah. Maybe i worded it poorly, but this thread i meant to ask "What applications thrive on thin oil, or Engine Designs" and "Which like thicker stuff."

GC seems to combine both worlds, so i wonder how thick people go with it. And if it is wise to use Thick 0w30 even GC in apps calling for 5W-40 and such.


Euro 5w40/0w40s and GC share the same/similar HTHS and meet many of the same specs.

Now in the case of API 5w40s, very few Xw30s have the same HTHS or specs.

 

[saberz]

Originally Posted By: aquariuscsm
I say no way! Or to better put it,I should say it depends on the type of engine,and the application the engine is used.


I was gonna say lol. What this man said is +1

 

[d00df00d]

Originally Posted By: HangerHarley
"What applications thrive on thin oil, or Engine Designs"

Tight clearances, strict tolerances, low oil temperatures, and no concerns about inadequate oil pressure or excessive contamination.


Originally Posted By: HangerHarley
and "Which like thicker stuff."

The opposite of the above.

Originally Posted By: HangerHarley
GC seems to combine both worlds, so i wonder how thick people go with it. And if it is wise to use Thick 0w30 even GC in apps calling for 5W-40 and such.

My application originally called for a 15w40 dino; now, BMW specs a 5w30 synthetic. My engine loves xw-40 oils, but I would have no problem using GC for the street because it is an acceptable viscosity as per BMW and carries the appropriate certification (BMW LL-01). If I were at the track, it'd be another story; I would opt for a good xw-40 just to be sure it could handle the higher oil temperatures.

Now, if my car said xw-40 and only xw-40, I wouldn't use GC.

I'm sure not everyone will agree with me. For an extreme example, there is a member named AEHaas who has used GC in his Ferrari Enzo, which specs a 10w-60. His rationale is that with his driving, his oil temperatures don't get very high, so he's better off with a thinner-than-spec oil. If I ever found myself in that situation, though, I wouldn't switch to a thinner oil; I'd sell the car to someone who would use it as it was made to be used. But that's just me.

 

[saberz]

Originally Posted By: HangerHarley
Originally Posted By: aquariuscsm
I say no way! Or to better put it,I should say it depends on the type of engine,and the application the engine is used.


Yeah. Maybe i worded it poorly, but this thread i meant to ask "What applications thrive on thin oil, or Engine Designs" and "Which like thicker stuff."

GC seems to combine both worlds, so i wonder how thick people go with it. And if it is wise to use Thick 0w30 even GC in apps calling for 5W-40 and such.



A thin oil for commuting, daily driver. A thicker/heavier(better term) for more harsh driving. Racing your car 10 laps around an oval at high rpm's. Occasionally wot driving can be used with a normal/lighter(weight) oil but not recommended.

I know that the 11 Ford Mustang GT generates a nice high HP figure and using the 5w20, but this is more for CAFE and street use. Yes Ford would not recommend it if it wasn't known to protect the engine. But I don't think it would provide the same protection as another oil to be used in high RPM applications for extended amounts of time with generous amounts of heat. By same I mean if you were to use a "racing oil" rather than "Motor Craft blend". You would need to service the oil sooner in either case but I am not sure which would come out on top in terms of "wear".

If you go to thick/heavy, you rob power from the engine and could potentially damage it from the extra stress caused by the weight. If you go to light(weight) I am not to sure on what could happen. The oil shearing further?

 

[Quattro Pete]

Originally Posted By: d00df00d

For an extreme example, there is a member named AEHaas who has used GC in his Ferrari Enzo, which specs a 10w-60.

I think he used M1 5w-20 and Redline 0w-20 as well.

 

[saberz]

And also drove in 1st gear up to 60 mph with moderate to low RPM's.

He wouldn't go racing with the 20weight.

 

[Quattro Pete]

Originally Posted By: Anies

If you go to thick/heavy, you rob power from the engine and could potentially damage it from the extra stress caused by the weight.

Seriously? Has anyone ever heard of a documented case where using thicker oil led to engine damage due to extra stress?

 

[saberz]

Quattro I am not stating it as fact. I meant it as "I guess" it could happen.

If you have a car meant for 20 weight and its components were manufactured to account for that viscosity and then you drop a 50weight in there, i think(guess) it would strain the components more would it not? Tolerances and such were made specifically for certain use.

I would figure having it under constant additional stress something would give after awhile(how long who knows). Or maybe nothing happens but the car would feel sluggish.

 

[hemitom]

Everyone should be made to read his(AEHaas) oil 101 at the front of this site, its a very good read, and really makes sense to me. There are things i never really thought of before. A rich man or not i applaud you for using your exotic machinery as test mules and sharing your findings with all of us here.

 

[mongo161]

If you want the true answer...I suggest that you read the 10 to 11 Chapters in the beginning of the "Bob is the oil guy" on oils. This can be found on the Home page.

From my take on the readings....It seems that light synthetic oil will fully lubricate your engine and will not break down in the viscosity department. Once a 10, 20,30 or 40 weight oil always the same weight oil. Synthetic oils may deplete their additive packages but will not lose viscosity. However, according to the article, the same can't be said for Dino oils which will lose their viscosity as well as their additive packages.

Heavy weight oils, if not specified for your engine, can really put stress on the engine and rob you of HP and also fuel savings and could cause damage.

IMO....the point that was made in these Chapters on the Home page is to use the lightest and best oil for your engine under your particular circumstances.

I would suggest for people in doubt, to please read the chapters on the home page. Then you can form your own opinions and come to your own conclusions.

 

[Tempest]

Originally Posted By: Quattro Pete

Seriously? Has anyone ever heard of a documented case where using thicker oil led to engine damage due to extra stress?

Exactly. Look at how thick ANY oil is at -40 and engines still pump this without any damage. The difference of any of the grades at operating temps is tiny in comparison.

Quote:
Everyone should be made to read his(AEHaas) oil 101 at the front of this site, its a very good read, and really makes sense to me.

It is highly flawed and should mostly be ignored.

 

[saberz]

Don't some oil pumps have issues pumping certain weights of oil?

So I had them mixed up then.(Was adding to it and saw the response below).

 

[Gary Allan]

It's got some things I don't agree with, but the writing does have a decent amount of quality content. The conclusions drawn may differ from the fine doctor's ....but so?

 

[21Rouge]

Originally Posted By: HangerHarley
And if it is wise to use Thick 0w30 even GC in apps calling for 5W-40 and such.


Consider CATERHAM's catchy mantra:

the oil should be as thin as possible and just as thick as necessary

Harley, this topic you have started in this thread was recently discussed here:

https://bobistheoilguy.com/forums/posts/1956110/

 

[Tempest]

Originally Posted By: Anies
Don't some oil pumps have issues pumping certain weights of oil?

Yes, thinner oils...which is why Ford still wants 30 grades in their 4.0's.

 

[hemitom]

Well Tempest, you explain how its higly flawed, You have the balls to call him out, you must have them to test oil on your high end cars as well, so have at it, post your results.