Originally Posted by Zonestar
.... If you have the 5.7 HEMI use 5W20 motor oil.
I wonder if oil viscosity should be the same in hot weather
... Owners manual doesn't tell a word about it. My RAM always used Castrol Syntec Blend 5W20, but I don't really know if these everlasting summer I live and drive in should make me go up in viscosity