I use oil from the dealer it's the best for my 540 IMO and I change it every 3000miles.

 

Tough to say, I don't know the climate of Azerbaijan very well. Change interval to be safe is 1 year or 4-9K miles depending on driving habits. Frequent drivers on long highway trips can go in the high range. Those that travel infrequently and take short trips (or track their car) should to short interval oil changes.

 

Hi Aspensilver540.
Azerbaijan climate is not so cold in winter its never pass -5 c lets say. This is maximum. For example this winter there is no snow and now is +11 c . So can you tell me which oil 5w/40 or 10w/40? Some our engineers or bmw driver says to put 5/40 till 100 000 km and if it pass then put 10/40 engine oil . But some of them says if engine is good put 5/40 even if passed 100 000 km

 

What are you trying to achive by using thicker oil? If you don't track your car I don't see any reason to switch to 10w40.

 

if the choice is between 5w40 and 10w40 definitely the 5w40 but there are other options too.

 

I just started using Mobil 1 0W-30 (Green label bottle). Runs smooth and I actually noticed increase MPG's.

 

But... the only oil that Mobil-1 makes that is approved for BMW's is their 0w40 European Blend oil that carrys a "BMW LL-1 or Long Life 1" rating.

OP I would use the 5w40 given the choice over the 10w40 oil. I would rather use a BMW approved oil though.

 

From the owners manual...it gives recommended oil viscosity as well as ambient temps: :dunno:

 

- How to logically choose the right motor oil for your E39
- How to philosophically choose the right motor oil for your PERSONALITY

 

Oh an Bluebee on my V8 it takes 7.2 to 7.5 qts of oil. 8 qts is too much.

 

7.9 is the spec btw

 

Between you and me, 6.9 and 7.9 is pretty much 7 and 8 to me because I'm not gonna leave 1/10th of a quart in the bottle on my shelf!