What oil do you use?

[claysones]

I have a 1990 325is with about 90k miles on her. She seems to not like synthetic oil and leaves drips of it periodically when I let it sit. When I use a non-synthetic it never leaks at all. thoughts on this? what oil do you guys run?

[SpecM]

I use Mobil One 15w50, but some good non-syn to use are Shell Rotella 15w40 and Castrol GTX 20w50

[Cabriolet]

you should be running 20-50 year round. non-synthetic. and replace it every 3k.

[berlow94]

Liqui-moly 5w40 baby!

[campbellj25]

I work at a bmw dealer and just put the same synthetic 5w30 I put in all the other cars. I agree it leaks worse than non synthetic.

[JinormusJ]

Mobil Delvac 15w40 Diesel Oil

Better than regular, thicker than synthetic

Has ZDDP additives that our worn out cams need, rated close to what m20s seem to like running (15w50+)



Don't worry about it being diesel oil; I know modded Supra guys that run it and swear by the stuff

[digger]

20W is too thick when cold even in hot climates

[golde30]

i ran castrol GTX 20w50 in my m20, and i beat the living shit out of it daily with no issues. was still running hard @ 200K when i pulled it.

[bastianshaw]

you should be running 20-50 year round. Non-synthetic. And replace it every 3k.

this
vr1 20-50.

[jeffnhiscars]

Penzoil or GTX 20-50, Mahle filter and a bottle of ZDDP every 3k. Total cost is $25

Nothing else makes sense to me

[LowR3V'in]

Vr1.
it's so good, it's not street legal ;)

btw, on both my m30s they both had the back cam lob warn down and
I bought a used 284 with the same wear on the same spot.

Probably filled with gtx or whatever non-rocker friendly oil it's whole life.

[digger]

oil threads lots of opinions..... unless you have controlled tests and proper lab analysis how does anyone on here know that wear is acceptable without tearing down the engine and measuring it and doing it for several oils and on more than 1 engine to establish a trend. Some guy uses xxx-yyy oil and engine seems to run fine for a while doesn't mean its a good oil or that a different oil wouldn't perform better.....

personally i would use at most 15W-xx for hot climates and at most 10W-xx for cold climates. a 40 or 50 will both work when upto temp and there are probably more important characteristics than the viscosity. but should change it and filter more often than what the book says

[audiquattrot]

Castrol GTX 20W50.

[Beau B]

Castrol GTX 20W50

[MF DOOM]

m1 15w50


EDIT: m42 car. somehow i missed that this was in the m20 section