[BackOnBlack]

Originally Posted by edycol

Absolutely DO NOT use any kind of FE oil on the track. Please, don't be that guy.

I hope not to be

I know that I am lacking knowledge in this area, which prompted me to ask this question. I am very appreciative of you and others taking the time to explain many details. Thank you very much.

Originally Posted by E90convert

To clarify any speculation on the BMW recommendation, I looked at the 2024 M3 CS owner's manual, and the BMW recommended oil is LL-01 FE 0w-30.

I also learned today that the 2020 M2 CS Racing specifies BMW LL-04 0w-30 with a 5,000 km track miles change interval and an HTHS ≥ 3.5. The manual lists Shell Helix Ultra ECT 0W-30
as an alternative. Here is the PDS for the Shell product, https://shell-livedocs.com/data/publ...d2d5349fa8.pdf

Expanding beyond engine oil, BMW specifies a 30,000 km oil change interval for the DCT and a 5,000 km for the Drexler rear differential, using BMW genuine fluids. There is no coolant change interval. These are track usage mileage only.

I saw the same thing in the manual, and I did not know what "LL-01" or "FE" meant, or more specifically if that is good or bad for my intended use. I also wasn't sure if those recommendations or specifications are for 'normal' use of track use. I am glad I asked the question

Thank you all, again.

[chris719]

Originally Posted by edycol

Street: Rl5W50
Track: RL 15W50.
In S65 or 85 if climate allows , I would go as low VI as possible. Arizona? 15W50, Chicago 5W50, and in summer 15W50. It will be more shear stable.

He has N55 though. I was just using S65 as an example of where I’d use that oil .

[edycol]

Originally Posted by chris719

He has N55 though. I was just using S65 as an example of where I’d use that oil .

Ah, got it.

[ericold]

Originally Posted by edycol

ZDDP is last line of defense once HTHS is not sufficient; meaning, viscosity breaks down.
That might fly driving a short trip from home to work, dropping kids to school. Actually there is pretty good evidence that low viscosity oils are better in short trips. It makes sense, the golden rule of lubrication is: As thick as necessary, as thin as possible.

i know you are talking about low 0-20 etc with lower hths.

in my case ,i told you i do a lot of short trips and a DI engine. i use 5-30 as we agreed. if i use a 0-30 thinner by visocsity=100c and lower VI=40C same hths 3,5,will it be better for short trips?
or bcs. hths in the oils i use x-30 dont have any diffrence at all bcs. hths is all that matters and both grades have same hths?

[edycol]

Originally Posted by ericold

i know you are talking about low 0-20 etc with lower hths.

in my case ,i told you i do a lot of short trips and a DI engine. i use 5-30 as we agreed. if i use a 0-30 thinner by visocsity=100c and lower VI=40C same hths 3,5,will it be better for short trips?
or bcs. hths in the oils i use x-30 dont have any diffrence at all bcs. hths is all that matters and both grades have same hths?

You won’t gain anything. 0W30 compared to 5W30 with HTHS 3.5? You are talking few cst at 40c.