i use castrol
20w50,
spring through fall and use castrol
5w30 up here in the MN
winters. i also add a bottle of lucas oil treatment in my old 93 rrc engine (specs are in the rrc manual) w/ a k&n filter. around the end of sept. or the start of oct. i switch to 5w30 due to the weather dropping at night (30-40's). we get some warm weather in oct (a couple of days of 70's-80's) but the winters up here can come fast and the temp drops...one day it's in the 80's in oct the next day 40's....got to lov it up here. this wkend it was in the 30's (1st time in wks) and on monday dropped down to -20
and it's going to drop even more by wed!!!!
