i just purchased a 91 850i and was curious as to which type oil would be best. the previous owner used mobil1 synthetic 15w50 is that the correct weight?

This depends on the weather, the 15w is ok for hot weather. I would recommend changing to a 5w/30, 5w/40 or a 10w40. If your engine is tight then a 5w should be great for cold starts and hopefully your engine will not consume.

"heavier" oils will make your lifters start making clicking noise. 15w50 Synthetic is okay.

thanks i think ill stick with 15w50

Mobil 1 0w30 or 0W40 provides the best cold start protection.

well i live in San Antonio texas so you never know about the weather today it was 80 and tomorrow it supposed to be 40

i just purchased a 91 850i and was curious as to which type oil would be best. the previous owner used mobil1 synthetic 15w50 is that the correct weight?

You should be good to go with the 15w50 down in San Antonio. Do you have any plans on April 11-13th, 2008?
A few of us here in Texas are caravaning down to Florida for the SouthEast 8 Fest in Mt. Dora. A real nice trip to meet a bunch of real nice people driving real nice 8's...

(basically, we aren't accepting excuses!) Plan on going !!

wow thats a nice car, i dont ive ever seen a white 8 in the UK