oil for cummins 8.3

[dirtroad2]

I have a Monaco diplomat with a cummins 8.3L I was told to use Rotella 15-40 W Can I use Rotella 5-40w synthtic

[john_bet]

I have been using Rotella synthic in my Cummins 5.9L for the last 150,000 miles and have had zero issues. I change it twice a year.

[RLS7201]

Read carefully Bob is the oil guy, motor oil university 101-201 and then decide what works for you.

Richard

[Johnny_G1]

In all my 50yrs trucking, I never ever seen cummins engine use anything but 15-40 oil and the oil I use is Delo 400 15-40, I think if you call and ask cummins they will tell you the same all though some guys are trying to use a synthetic oil today. Just my thoughts.

[64thunderbolt]

absolutely and your eng will thank you & repay you with better cold starts and long life.

[Ductape]

Yes.