Author Topic: best oil for boosted ap? (Read 3250 times)

persianbmw · « **on:** March 15, 2010, 10:53:37 PM »

i currently have 5w30 sythetic blend. what brand is recommended and weight for summer use. also factor in the turbo idk if its relevant

Ryann · « **Reply #1 on:** March 15, 2010, 11:57:07 PM »

My factory '91 e30 318i manual recommends 15W-50 for temperatures between -5F to 110F, 20w-50 between 15F and 120F. It shows 5W-30 for temps between only -40F and 25F. In my experience turbos increase oil temperatures substantially (hence added factory oil coolers on my SAAB 900's), so I'd tend choose an oil rated for higher ambient temperatures if I were you.

rob_e30 · « **Reply #2 on:** March 18, 2010, 06:26:42 AM »

We run Mobil1 15-50

persianbmw · « **Reply #3 on:** March 28, 2010, 11:55:08 PM »

wat are the down sides of having such a high viscosity

dwtaylorpdx · « **Reply #4 on:** March 29, 2010, 09:26:05 AM »

None of the M42's have their bearing clearances set up for the new thin oils. It will increase wear in most cases.

The guy who builds race engines for the shop I play out of is very
specific when building a engine to verify which oil is to be run.

Dave