I know this is likely to start a war in some forums, but please indulge my newbie question. I've just started doing my own oil changes on my E90 M3. The recommended oil for this car was Castol 10W-60. In doing some reading I see that Castol is now no longer recommended by BMW and I've also read that Shell Pennzoil Platinum 5W-40 full synthetic is recommended by some, as it might help ease the potential for the dreaded ring bearing issues in cold weather climates. My car is purely a street car and living in NC we really only get cold temperatures for maybe a week or so per year, so I'm really not so afraid of high oil viscosity giving me cold temperature lubrication issues. What's the consensus on this topic, is BMW still sticking with 10W-60, or is 5W-40 now the go-to oil choice? Any guidance would be very much appreciated!
Yes BMW has switched oil suppliers and some viscosities of oil. 5w30 is now 0w30 and 0w20. If you let your vehicle warm up properly before driving off makes the biggest difference when using the 10w60 oil in colder climates. 60w will provide better protection on warm engine temps when compared to the 40w. But in colder climates the 5w will do better for protection on the cold start than the 10w. I recommend sticking with the 10w60 and just letting the vehicle warm up.
Thanks for the guidance! Oil analysis is showing no signs of metals, or engine wear, so the recommendation makes sense. Good to know that I'm not missing anything by not switching.
