Flashman wrote:
Cummins12V98 wrote:
Flashman wrote:
Flan wrote:
Do not use 15/40 oil under any circumstances. Fresh def. plan on getting filters and oils ahead of a service they are becoming harder to find due to supply chain issues. Keep idle time to a minimum. Exhaust brake is her friend. Same with tow haul.
What's wrong with 15/40??
They went to hydraulic lifters since 2019 and 15/40 is now No Bueno!!!
Still good for my 2017?
Nothing wrong with 15/40 on your 2017. 5w/40 or 10/30 (temp dependent) is the oil needed for the 2019+ CGI engines with the hydraulic lifters. 5/40 T6 rotella is a great all around oil for the widest temperature ranges.