It happens to me aswell, I have spent many hours searching threads and asking questions here but have had no real luck in finding an answer. I have had my engine compression tested and no results with that either.
There are a few things I have done to reduce it, I changed the oil seporators and hose's and switched form castrol tws to castrol edge 10w60 rs.

 

Andy

I might move over to Castrol at the next oil change. I replaced the seperators about a year ago - they were pretty sludged up. I might have a look at the hoses too.

 

I too was going to suggest the oil separators....
+1 on the hose inspection and replacement.

 

Hi :byee55amg, did you verify your spark plug? When you decelerate, your engine create vaccum in the intake and some time if your valves seal are used the oil will go thru. I hope for you that is the problem because if not, that mean your cylinder are probably scratch, mine was smoking a little bit when I was whipped the throttle on idle, I also had a light knocking, so I took all the compression on all cylinder to make sure, they was all around 200 +/- 5 PSI, result engine was blown oohhh: . Ok the car was salvage but anyway. By the spark plug, that will give you a good idea, mine as a big difference of carbon accumulation between each other and also after put new one and run the engine on idle and whip the gas couple of time, I took off the plug again and they was already with oil deposit. See the picture below of my engine damages. I hope for you that is not that case.

Sonny

 

Thanks Sonny. No knocking, but yes could be my valve stem seals. I would expect smoking at other times though.

 

Is the smoke blue or black? Blue usually means burning oil, but black is carbon which would not be unusual for an m5.

 

Definately blue - definately oil.

 

try switching to thiker oil and see if that solves your problem. If it is not happening all of the time thiker oil will usually help slow the consumption of oil. If you are already using Mobil 1 then I would suggest you go to the 15w-50 and see what happens. unless you are already using that weight of oil. Then, I donno what to tell you. Good luck!!!

 

Dino

I'm running 0w40 but I think I'll move to 10w60 at the next oil change.

Max

 

0W40 oohhh: !!!!!! I really don't think that is a good idea to run these engine with that grade of oil even is the best company made it, the cylinder are made from aluninum and the clearence are quite tight and also I don't think that is good for the vanos actuators, I will suggest to run with the factory castrol TWS, I also seen Penzoil, they are made a grade for race application, 25W50 and it's about 6-7 dollards each pint. I will suggest to do your oil change right now, I also know the boss of Techlube distribution, is Motul Canada basically, I ask him if motul have a grade for the M model, he clearly said to use the factory TWS and nothing else... I was really surprised but I think he right...

Sonny :cheers:

 

My BMW main dealer in the UK only uses Mobil 1. My beast has run with Mobil 1 for the last 70,000 miles and now I have nearly 130,000 on the clock.

Perhaps I should start topping up with 10w60, if mixing grades is acceptable?

 

Will all due respect to others, Mobile 0W40 is perfectly acceptable.

However, I don't recommend mixing two different brands of synthetic as it may cause foaming. At your next oil change, switch the oil (if you so choose) to Castrol 10W60 and use the oil to top off.

Basic rule for repair--inspect the cheapest thing that can cause the problem and go from there. Oil separators are relatively simple to remove and check. If filled with much, clean out with carb cleaner and spray clear with air. Reinstall.

 

Will all due respect to others, Mobile 0W40 is perfectly acceptable.

Agree with everycredit.
Mobil 0w40 has BMW LL01 approval.
Mobil 1 0W-40

From what I read here, Mobil 0W40 is somewhat close to BMW 5W30 oil.

 

I had this issue on my motor bike. Yup. Stem Seals.

 

Hi Max.

My car ran TWS and I tried 0W 40 mostly due to Douglas Bakers recommendations. He loves Mobil 1 so much he has it on his shreddies.

I tried it and my car burnt it like water. Not quite as much as you but previously my car burnt none at all.

I only kept it in there for for 5k miles before changing back.

My car then burnt the TWS but at a lower rate than the Mobil1 but still burnt it none the less.

Gradually, very gradually the oil consumption has reduced, now - probably about 2 years after I drained the Mobil 1 - it barely burns any at all. Werid eh?

Personally I think 0W 40 is way too thin but Doug Baker swears by it. One can only assume that although our cars are the same in spec, they have their own running attributes.

I say switch to the thicker Castrol TWS (EDGE) ASAP and see what happens.

Neil

 

Oh, just saw this is an old thread revived.

 

Neil

No worries. I did switch to TWS and consumption went down. I have just completed my insp. II and guess what, the dealer has switched me back to Mobil 1. I will update you on consumption this time once I have covered soem miles.

Max