Just curious what engine you are running...oil temps and pressure....are you set-up to run that low of a viscosity..journals..oil pump...coolers? If you are running 11 qt oil pans and a high volume pump you may be ok with a Super premium Synthetic 5W-30 in a big marine engine.Originally Posted by Papache
Just curious. the lowest viscosity I have seen used is a
10W-40 Super Premium.
Illmor tested the Dodge Viper marine engines and found the 10W-30 for street was not sufficient to develop a proper film at constant nearredline use.. so they moved up to 15W-50 Mobil-1.