What weight oil do you use?

[Don and Kim]

Reading the owners manual for our 06 and noticed both 15w40 and 10w30 is recommended for the C7. Being new to the diesel world, I thought 15w40 was the "universal" oil weight used.
Don

[bob109]

Quote:

Originally Posted by Don and Kim Reading the owners manual for our 06 and noticed both 15w40 and 10w30 is recommended for the C7. Being new to the diesel world, I thought 15w40 was the "universal" oil weight used. Don

Stick with the 15w-40. Much better protection than 10w-30

[Poptop]

I have a 2005 with a CAT 300 and the manual says 15-40 unless you're operating in temps too cold to be in!