Originally Posted By: CATERHAM
Originally Posted By: dailydriver
Also, the RL 5W-30 you want to use is the same exact HTHS viscosity as the M1 0W-40 in your sump now.
The N52 engine does not require a heavy 3.8cP HTHSV oil and RL 5W-30 is actually heavier on start-up than M1 0W-40.
I suggested RL 0W-30 (same POE/PAO, high moly, high ZDDP chemistry) for it's more appropriate 3.2cP HTHSV and similar VI to M1. It's a shear stable oil that has an operational viscosity on par if not higher than the BMW 5W-30.
In fact if it were my car, my RL oil choice would be their 0W-20 as it really is a light 30wt with the same viscosity as the BMW LL-01FE 0W-30; and that's as heavy an oil as necessary for street use in the OP's car.
I was not even considering specs, or requirements, just commenting on that there is no operational full temp viscosity difference between those two oils he was comparing.
Originally Posted By: dailydriver
Also, the RL 5W-30 you want to use is the same exact HTHS viscosity as the M1 0W-40 in your sump now.
The N52 engine does not require a heavy 3.8cP HTHSV oil and RL 5W-30 is actually heavier on start-up than M1 0W-40.
I suggested RL 0W-30 (same POE/PAO, high moly, high ZDDP chemistry) for it's more appropriate 3.2cP HTHSV and similar VI to M1. It's a shear stable oil that has an operational viscosity on par if not higher than the BMW 5W-30.
In fact if it were my car, my RL oil choice would be their 0W-20 as it really is a light 30wt with the same viscosity as the BMW LL-01FE 0W-30; and that's as heavy an oil as necessary for street use in the OP's car.
I was not even considering specs, or requirements, just commenting on that there is no operational full temp viscosity difference between those two oils he was comparing.