2008 Dodge Ram 1500 quad cab 4x4 hemi
 

Hello everyone! Can't believe I just joined this group! I am the original owner of my truck, looking for answers to the transmission issues I have had when towing. The dealer mechanic says it is limp mode when the trans gets hot, it only has 2nd, third, and reverse. I believe I have the .390 gears and it came with the tow package. I want to know if there are any upgrades I can do without voiding the lifetime powertrain warranty. Thanks 😊

Welcome to DF! Moving this to third gen ram section for ya.

Thanks!

I have heard that the tranny coolers for the 5.9L diesel is larger than the 5.7 cooler, and will fit in the existing mounts. I haven't seen it personally, maybe someone with experience will chime in.
When you say the "trans gets hot", do you mean overtemp with a caution light?
Are you operating in severe towing conditions? Hot weather, hilly conditions, heavy loads?
If the conditions are bad then a larger cooler may be the fix. If not then I'd rec troubleshooting your tranny. Start with reading tranny temps with a code reader, then dropping pan and doing visual inspection of fluid and trans body.

The Transmission only does the limp mode thing when towing. After cooling down, it acts fine. Never any codes for dealers to read, or me. I will try the bigger cooler first since it will not void my warranty. If that doesn't work I will bring my scan tool with me next time I have to pull the camper.

It's the 545RFE hemi cooler for the 3500:

https://cimg0.ibsrv.net/gimg/dodgefo...e368ea1a3e.jpg

Yep, that's the one Magnoom.
I recommend that you get a reader or dongle that displays trans temp. Pull over when you hit 220F or so.
I'd also suggest a pan drop tranny fluid change every year.
I assume you are using tow/haul mode to lock out overdrive.

Welcome to the forum

Thank you for all the assistance! I will be getting that trans cooler since the dealership mechanic say it will not void the warranty. I will monitor trans temperature next time I am towing to make sure it is good to go.

It's part number 52029089AB. Also a finned trans pan doesn't hurt either:

https://cimg7.ibsrv.net/gimg/dodgefo...ee27663316.jpg