Just curious what the board consensus is on the "correct" fluid for NV5600 6spd in 2002 Cummins ?? The "factory Mopar" 4874464 fluid @ YIKES $$$ ??? Or something like the Valvoline Synchromesh Fluid that states it can be used in place of factory fluid ? Time for fluid change and don't recall what to use ?? I am going to put on a "Geno's Garage" transmission cooler and add 1 xtra litre to transmission . . . as seems most say the transmission could use 1 extra litre, and I am always happy to have some extra cooling. Truck is totally stock 2002 Quad Cab, HO, 6spd.

Thanks,

Hi A12 , Yup that Mopar Fluid 4874464AB is great stuff ! and a LOT cheaper than a New Transmission from using the wrong or cheap Fluids ! The Pennzoil Synchromesh is also Great Fluid , and a few bucks cheaper . Ronnie

Be careful Mark. The "right" fluid is cheap compared to potential repairs. Parts for the NVG 5600 have been tough to come by for years. I think production ended in 2005? So near 20 years since they quit making them. I quit floating the gears in mine for fear of screwing up the syncros. I _think_ my expert used Redline MTL synthetic in mine but the memory is iffy and I gave up my maintenance and modifications file when I sold the truck so can't look it up anymore. My other expert is a big Amsoil advocate, I don't recall ever discussing this trans and Amsoil with him. That might be an option to look into?

Pennzoil synchromesh

Thanks . . . from what I have seen on the websites, its either Pennzoil, or the factory fill . . . gonna check with my local dealer and see what they have/can get . . .if not, then Pennzoil. Yup, don't want to screw up the tranny for sake of a few $$ saved on fluid.

Well, dealership has fluid in stock, gonna be $250 (Canadian Funds) . . .BUT, that's way cheaper than having the tranny go !! . . . oh the joy !!

LOL . . .

Its the cost of owning the best (?).
I just bought ATF 4 for my beater 4x4 pickup, 9 quarts at nearly $9.00 each at the local parts store, just under $90 for the fluid & tax alone, then I have to get under there and change it myself.

I also just changed the fluid in my 90 NV2500, it takes 2 quarts 10 W 30 motor oil, that is cheap enough. But putting 2 quarts of motor oil into a manual trans that is still in the vehicle is not an easy task if you don't have a suction gun, and are laying on your back under the vehicle. I made a big mess out of that one. I'm growing tired of getting under my stuff, the idea of sipping on a soda in a nice cushy chair in a nice waiting room while someone else is doing the dirty work under my stuff is growing in appeal.

Oh I know what you mean . . . specially when getting under the truck seems tougher each year. I swear the springs must be sagging cause the truck is closer to me ! . . . ha ha ha . . . yeah, gotta get under drain it, fill it, etc. . . but I just can't bring myself to pay a shop rate of $150/yr for something I can do . . . Besides,what else do I have to do ?!?!?! lol

seems a lot of guys like Amsoil Manual Synchromesh Transmission Fluid (MTF) overfilled to 6qts through the shift tower.
i am going to try it.

Thought that was the “trick of the day” for the old Getrag with that tiny rear support bearing.