... Coming up on 30K miles on my '04 Dodge Cummins

Never serviced the auto transmission other than keep fluids level.

What's the best ATF for here on out?
Amsoil, makes no difference, other?

 

I LOVE teh Amsoil I'm using in my new tranny. I've been abbusing the hell out of it and it is staying good. Not the cheapest by a long shot but do it once and do it right!

 

Been using Amsoil ATF in every Dodge trans I have owned for the last 9 years and I have never had a problem from using it. IMHO its the best ATF made.

 

Good stuff You're in luck if interested. Prices just went down 2 hours ago. Can shoot one if you become interested.
Heath

 

Amsoil by far! I use their ATF, 15w40 hd motor oil with their micro media or whatever they call their filter. And also their gear oil for my diffs. I forget what weight that is.. seems to me like 80w or somthing like that. The gear oil smells rank.. but its good stuff!

 

I run Amsoil also. It sure made my trans run smoother once I got the factory fluid out.

 

Amsoil or Royal Purple

 

Amsoil's ATF & Marine 15W-40 are about the best according to Team XLR8R's lube engineer, but we use SynerGyn fluids in the race truck.