I still prefer 0w-40 over 5w-40 just because it usually contains better base oil. Specifically higher amount of PAO. Group III oil cannot have pouring temperature below -48C .
The thickness of the oil when we just start up is 10× or more thinner than when the engine is warm >70C. The cold start up and early lubrication is the most important factor in engine wear.
The thickness of the oil when we just start up is 10× or more thinner than when the engine is warm >70C. The cold start up and early lubrication is the most important factor in engine wear.