Did I kill my OM617 with oil?? - PeachParts Mercedes-Benz Forum

JHZR2 · #1 07-18-2011, 01:42 AM

Quote:

Originally Posted by leathermang

" Recommendations " are now influenced by the need to maximize corporate mpg stats... NOT for longevity.. they do not care... in fact will be pleased to have your MB wear out a little faster so you can buy another one from them...

Give me a break. Really?

Is that why trucking fleets run 15w-40 over SAE 40?

Fuel economy in those tests is ruled by the 100c oil viscosity. Guess what? A 5w-40, 15w-40 and SAE 40 are all the same viscosity at 100c.

It is far better to have adequate flow as fast as possible under any conditions.

And if you look at any UOA from any HDEO, youll see that it retains proper viscosity over a LONG time... It would be one thing if they weren't shear stable, but they are.

So what exactly do you think y ou're getting out of running a straight weight? 30 years ago there was bona fide benefit. Things have changed just a bit, and oils are more than a little but better now.

leathermang · #2 07-18-2011, 03:14 PM

[QUOTE=JHZR2;2753638]....It is far better to have adequate flow as fast as possible under any conditions./QUOTE]

If you really believed that you would have a PreOiler on your car... just like many trucks do....
Do you have a preoiler ?

JHZR2 · #3 07-23-2011, 11:30 PM

[QUOTE=leathermang;2753876]

Quote:

Originally Posted by JHZR2

....It is far better to have adequate flow as fast as possible under any conditions./QUOTE]

If you really believed that you would have a PreOiler on your car... just like many trucks do....
Do you have a preoiler ?

I really believe it and I don't. Have you looked at the differerence in viscosity between an sae40 and a 5w-40 at 40C?

Rotella 15w-40 is 120 cst at 40C
Rotella SAE 30 and 40 are 107 and 120 respectively.
Rotella 5w-40 is 87.

So if were talking a hot day, which one will pump faster/easier?

When it gets cold what do you think will happen?