stevenP
Senior Member
- Joined
- Nov 9, 2014
- Posts
- 641
- Reaction score
- 621
- Location
- northern Indiana
- Ram Year
- 2022 2500 Longhorn
- Engine
- 6.7L Cummins
So I had a Gen4 cummins. Now I have a Gen5 6.7L cummins in my new 2500. So I see that the recommended oil is now either 10w-30, or 5w-40. The thing is I have a lot of the rotella 15w-40 oil in jugs still. Should I not use this in the summer season?