[NIsaacs]

This is what I use. Should be just fine where you live. I buy it from Cummins, free shipping over $75. Napa carries it here, but kinda expensive.

https://shop.cummins.com/CSSNAStore/s/categories/a224N000007v0yWQAQ/Valvoline Oil

 

[NIsaacs]

. The big price jump happens going from T-4 to T-5. Stepping up to T-6 is a much smaller increase. Not enough savings to justify not buying T-6 over T-5 IMO.

Thats the beauty of the Valvoline Premium Blue 10/30 synthetic blend, it is $17.50 v/s the full synthetic 5/40 @ $30.