i have a 1990 Chevy Silverado with a 4.3L 262ci Chevy V6 that has been rebuilt. i am running 10w 40 castrol regular oil throug it and it run and sounds fine when it is cold but at temp when idleing it will drop to 0 and i can hear a knocking. i was wondering if i should put a thicker oil in it like straight 60 weight racing oil or 30 weight.
Dec 12, 2010 at 11:53 PM
