2002 525i Oil Viscosity

[Chris Lovell]

I just changed out the Mobil1 5-30 with Mobil1 10-30. Sounds insignificant btu we are heading into cold weather and the Owner's Manual calls for 5-30 synthetic. Should I stay the course of change to 5-30 now? Basically, I am not sure how finicky these engines are.

[Jeron]

I wouldn't say the engine is finicky. I used to run 10w-30 summer and 5w-30 winter. I just run 5w-30 year round now in my E46.

I'd leave it unless you park outside at night.

Take some solace in that Mobil 1 runs thinner than other brands.

[Chris Lovell]

Thanks. I'll do as you say and let it go. Or I could just swap out the 10-30 from the crankcase and replace with 5-30. Easy, but without filter, a little incomplete. I must be bored to be worrying about this stuff.

[Jeron]

If you just changed the filter there is no need to change it again.