Hi bitogers, just picked myself up a BMW 1M. It has the N54 engine in it, and yes it runs rather warm oil temp wise. My car does have a factory oil cooler and oil temp gauge, but the thermostat for the oil cooler opens quite high, and cruising oil temps in ambient temps of 15-30*C are approximately 115*C (239*F). However the oil cooler seems to do a decent job, with oil temps not exceeding 120*C (248*F) when driven spiritedly in the hills. Although 120*C isn't super high for a high power turbo car pushed hard, the normal operating temp to me does seem high. My 2003 Evo 8 (320wkw on E85) cruised at 88*C and my Golf R cruised at ~92*C. I'd hit 115*C in the hills with the evo, and around 110*C in the Golf.
I can do a mod on the oil cooler thermostat to have the oil cooler constantly used, but warm up times and cruise temps are impacted, with cruise temps post mod around 93*C and warm up times increased. This scared some off it, personally I think 93*C is fine for cruise, temps would head over 100*C when pushed for sure.
I've read the following 335i thread where fuel dilution and oil temps were off the chain, exceeding 140*C. Some 335i's did not have an oil cooler from factory and some did, so not sure if the temps reported in the below thread are reflective of a vehicle equipped with one or not.
http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/981162/13
However that thread ends in 2009 and I was wondering what the current thoughts are on this engine.
I am worried about the condition of my oil and now that the car is in my possession, and given I plan to keep it long-term I want to establish an appropriate OCI and choose the most suitable oil.
Right now, I am thinking of doing 5000 - 10,000 OCI with German Castrol 0W-30 (Belgian made) as it's ~$98 per change (sump volume = 6.5L) then doing a UOA to see how it's going.
Any thoughts on other oils or current data on this engine are welcome!
I can do a mod on the oil cooler thermostat to have the oil cooler constantly used, but warm up times and cruise temps are impacted, with cruise temps post mod around 93*C and warm up times increased. This scared some off it, personally I think 93*C is fine for cruise, temps would head over 100*C when pushed for sure.
I've read the following 335i thread where fuel dilution and oil temps were off the chain, exceeding 140*C. Some 335i's did not have an oil cooler from factory and some did, so not sure if the temps reported in the below thread are reflective of a vehicle equipped with one or not.
http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/981162/13
However that thread ends in 2009 and I was wondering what the current thoughts are on this engine.
I am worried about the condition of my oil and now that the car is in my possession, and given I plan to keep it long-term I want to establish an appropriate OCI and choose the most suitable oil.
Right now, I am thinking of doing 5000 - 10,000 OCI with German Castrol 0W-30 (Belgian made) as it's ~$98 per change (sump volume = 6.5L) then doing a UOA to see how it's going.
Any thoughts on other oils or current data on this engine are welcome!
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