We've got a 2006 2500 with the Cummins diesel and a standard tranny (GK56 by Mercedes). What kind of tranny fluid does it use? One place tells me to use ATF-4; another place tells me to use straight gear oil.

We're getting ready to put a clutch in it, and I don't want to ruin the tranny afterwards!

Thanks.

 

Check your owners manual. I do believe it is ATF + 4

 

Should be stated in your owners manual. If you don't have one, you can go here and download one for free.


https://www.mopar.com/ramtrucks/en-u...er-manual.html

 

You may use ATF+4 or Valvoline Max life ATF fluid, the Valvoline fluid covers the ATF +4 specs and may be cheaper. DO NOT USE STRAIGHT GEAR OIL!

 

Apparently, that's a manual tranny. ATF may not be a good idea.

 

Sorry, if it's manual gear Oil would be required. Just need to find out the correct weight.

 

Better check. Many manual transmission use ATF

 

Okay Benz recommends 75/90 gear oil. Ram says ATF +4. IMO I would use what Benz says. They built it.