I'm curious why 10w over 5w? IIRC, (i don't have my list in front of me), 5w40 made the Oil TSB but not 10w. The 05w40 syntec is being processed for approval. I'm assuming they made a change to it?
Jim
Quote:
|
Originally Posted by JFP in PA
We use 10W-40 year round, and it gets plenty cold here in PA in the winter. If you go to Castrol's website, their tech specs for the 5W and 10W oils are not all that different in the cold; so unless you are going to see sustained -25F (or worse), I wouldn't worry about it.
|