Thanks for all the replies.

The car is a very late, 4/99 M3 build, so it's an S52.

I'm going to start by trying the M1 0W/40 and see what happens. If it sucks, I'll try the next suggestion and take it from there.

Let you know...thanks!!!

If the M1 0W-40 does not reduce the somewhat common oil consumption experienced when these engines are run on reg M1 5W-30, you could try:

M1 High Mileage 10W-30 or 10W-40 or
Mobil 1 TDT 5W-40 (don't be afraid of the diesel specs listed. The M1 0W-40 is also rated for some diesel engines.)

These are readily available at some auto parts stores and Wal-Mart.

One more good, but relatively inexpensive synthetic to try would be Rotella 5W-40 synthetic. It always does well in these engines and the price is $19/gal at Wal-Mart.

My S52 burned/consumed oil when it ran 0w-40.
It is much happier running Mobil 1 TDT 5w-40 (similar to delvac or rotella I believe)

I've heard good things about the M1 5w40 in these cars. How bad of a hit mileage wise did you take using the 5w50?

Have 1999 528iT, M52TU w/52M miles, uses GC with 7500 mile oil change intervals. Used Auto Rx w/ Delo 15w-40 for a cleanup treatment after car was purchased w/27M miles. Previous oil used prior to purchase was BMW 5w-30. Delo makes it run mighty quiet.

was this question directed at me?
i honestly don't know, because i drive my M3 the way it was built to be driven and I rarely check the MPG except on long trips.

Well after 1000 miles with Mobil1 0W-40, it looks like I burned 1/2 quart. Not too bad.

I'll keep an eye on it....

not huge since i only topped about half a liter....i do not have exact mileage but the type of routine driving i had been doing during that time.....i was filling my tank once every two weeks....but after topping 5W-50 it was more like getting my tank full with gas the 13th day...

BMW Power:

Check the crankcase venting system or have someone else check it. That engine has a complex system that includes a cyclone to separate oil droplets before returning the crankcase vapours to the intake to burn.

I have a 2000 Z3M with the S52 engine. My car was using lots of oil until I unplugged the PCV system drain back to the sump via the dip stick tube.

I am having great results with Maxlife full synthetic 10W30 which is LL01 approved. I am at 2500 miles into my current OCI and the dipstick level has only dropped about 1/8"

thx MVA!

Reviving an old thread as it is relatively pertinent. I have an S50 powered M3 (95) that has run lubro-moly 0w-40 for years upon years.

I have another change coming up and wanted to try GC out as it is locally available, however I have hestitations due to the doom and gloom stories on some M3 boards members have about 30 weight oils (M1 5W-30) in these motors not providing enough protection and contributing to some failures on heavily used cars (HPDEs, Autox, etc).

I have seen GC is closer to a standard 40 weight, but would just like to hear some chime in if they have used it on the US spec S50/S52 motors with success.

M1 5W30 doesn't meet spec for a non-M engine (to thin and HTHS to low) amd it's so far off spec for an S52 engine it's ridiculous. Why not just put the corerct oil in it?