m325i 709 Report post Posted February 19, 2020 You may have seen this guy online who has rebuilt the most v10 m5 motors in the world. He is preaching using a hotter thermostat and 5w50 oil and claims it basically nullifies bearing wear. What are you guy's view on this? I've seen some e46 m3 guys switch to this oil - but I'm wondering how you can really tell the effect, (if 10w60 and stock bearings can last, say 200km+, then you would need to to 100km+ to prove reduced wear?) Quote Share this post Link to post Share on other sites
aja540i 1906 Report post Posted February 20, 2020 From what I understand the bearing wear issue is caused by very tight tolerances between the crank and big ends, not by BMW specifying the wrong oil, so changing to a different weight oil and running the motor hotter may reduce the effect of the tight tolerances but it doesn't make them go away, and it could lead to other problems in a very complex engine. If doing this makes you sleep better at night then go for it, but it wouldn't fill me with confidence! Quote Share this post Link to post Share on other sites
