Originally Posted By: 05foresterXT
Considering the dubious 20w40 & 20w50 I have yet to respect anything I read in car manuals regarding oil viscosity. I can only respect the required viscosity to run which in this case is 5w30.
Granted the Synpower SN came in at 9.4 which is the bleeding edge for a 30 but the AFE 0w30 with it's superior basestocks did much better at 10.4 after hard use. Yet this was the oil I was told would be my downfall...in flames.
I should add that while running a 0w40 isn't required even modified it sure as heck can't hurt but if you can't find a 0w40 in a crisis moment good 5w30(or 0w30) synthetic isn't going break rods & shatter ringlands either.
Considering the dubious 20w40 & 20w50 I have yet to respect anything I read in car manuals regarding oil viscosity. I can only respect the required viscosity to run which in this case is 5w30.
Granted the Synpower SN came in at 9.4 which is the bleeding edge for a 30 but the AFE 0w30 with it's superior basestocks did much better at 10.4 after hard use. Yet this was the oil I was told would be my downfall...in flames.
I should add that while running a 0w40 isn't required even modified it sure as heck can't hurt but if you can't find a 0w40 in a crisis moment good 5w30(or 0w30) synthetic isn't going break rods & shatter ringlands either.
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