oil change

[MikeVictor]

Nice chart, Dack.

[sparoz]

After much research awhile ago, my opinion is that LL1 doesn't really matter as long as it is changed before it breaks down. For example the TWS is not LL1 and needs to be changed every 8000km.

However most of us plan to change sooner than schedule - LL1 is not necessary as long as it is a good oil. I am not going to debate what is a good oil as I only ave an opinion and data is not clear but my plan is to do oil analysis at the change so that I can get some data with my car and my driving habit.

There was an interview with the head of M engineering and it was asked why TWS is not required in the N54. His response was that oil can start to break down if the engine oil temp is over 150c. Although the engine in some parts reaches up to 200c it is only for an instant and not sustained like the M3 v8. It is the breakdown of oil that potentially causing the problem.

Comparing viscosities, the redline page has some good info on hp and oil. Basically there are a few ponies between the different grades.

As I don't track my car, and drive only a short distance, I am most likely start off with 5-30.

[UR25IO]

Originally Posted by TimMc

Just use whatever's on sale at K-Mart. All oils are the same. And there's no need to change oil more often than the specified 25K.

LMFAO....
you always come up with the best answers

[Dackelone]

Just some more info on BMW recommended oils...

BMW-Oil-Specs-and-Recs.pdf

BMW_Oils_CurrentListing_of_SyntheticOils.pdf

[Mechz]

Originally Posted by Dackelone

Some of us "gear heads" prefer to change our oil more than what BMW says to. To my thinking... new oil is the best oil!

And... I would only use an oil approved by BMW(full synthetic). That means: BMW long life 1 (LL1) with API: SM / CF, ACEA C2, C3 in any of these grades: 0w30, 0w40, 5w30 or 5w40. The most important thing is to use an oil with BMW LL1 rating.

So why do you listen to BMW on the type of oil they recommend but not when it comes to how long that oil will be good for use?

Just trying to see the logic here.

[Dackelone]

Originally Posted by Mechz

So why do you listen to BMW on the type of oil they recommend but not when it comes to how long that oil will be good for use?

Just trying to see the logic here.

Because... I am old enough to remember when BMW first came out with V8 engines in the e34 and e38 series. Those engine's had Nikasil sleves in the block. Long story short... it was the high sulfur fuels in the USA and (poor)oil quality that caused premature wearing of the engine bores/sleves. BMW ended up offering new engine exchanges to anyone who knew to complain about hard to start engines, low comporssion or exsessive oil burning. They did not do a recall but a service action for anyone who complained when their car was in for service.

That was when BMW started to do alot of testing of engine oils. That was also when you started to see the "BMW reccomends castrol oils" on the engine oil fill caps.

THAT is why it is so important to use BMW Long Life rated oils. Not becuase of a long OCI (which is one more reason) but bc of the engine wear with dissimilar metals inside BMW engines.