I know that the recommended oil for our trucks is 15-40.
Where does 0-50 synthetic come in? Is this acceptable for our engines?

Got 5w40 Rotella (synthetic) in mine right now for the cold weather, I'll probably switch back to 15-40 when the temps get warmer in the spring.

The options listed in my owners manual are: 5w40, 10w30, and 15w40.

I use 0w30 all year long.

I have never heard of a 0w-50 synthetic, especially not one with CH-4 or CI-4 ratings.

Our Canadian friends, such as PowderKing, have options open to them not available to those of us in the USA. Imperial Oil, which is the ExxonMobil Canadian affiliated company, makes and markets some fine diesel oils under the Esso XD-3 label. They are available in a number of grades with CH-4 and CI-4 certifications, including 0w-30 and 0w-40 multi-viscosity.

http://www.imperialoil.ca/Canada-English/Files/Products_Lubes/IOCAENCVLESEsso_Xd-3_extra.pdf

Yes i worked for Imperial oil as a lube monkey(i no that sounds bad) but anyways yes the closest we can get to that is 0w40. The only thing i ever saw with 50w was mobil 1 15w50 and then there was esso for the gas engines you can get 20w50. That is really only for summer use only in hot climates.

The 0-50 that I am referring to is at Costco (Alberta Canada) which is a Castrol brand.

The reason that I have asked is a buddy of mine ran this stuff in his Jetta.

I will have to have a closer look for all the c/ch ratings

I've run John Deere Plus 50 (synthetic) 0W40 all year long with great results. Oil analysis have always come back clean. I have'nt come across a 0W50 so far. Is it labelled as a Kirkland brand made by Castrol?

I've run John Deere Plus 50 (synthetic) 0W40 all year long with great results. Oil analysis have always come back clean. I have'nt come across a 0W50 so far. Is it labelled as a Kirkland brand made by Castrol?

Castrol