T Tomas New member Nov 15, 2009 #1 I accidentally put 10w-40 Castrol Edge full synthetic in my 1988 Ford Ranger when I usually use the 5w-30 it requires. Will the 10w-40 hurt the engine at all. That Castrol Edge stuff is expensive so if it is OK to use I will leave it.
I accidentally put 10w-40 Castrol Edge full synthetic in my 1988 Ford Ranger when I usually use the 5w-30 it requires. Will the 10w-40 hurt the engine at all. That Castrol Edge stuff is expensive so if it is OK to use I will leave it.
