sinawalli

How often does anyone change their diff oil? What are the capacities of both diffs, and what is the best type of oil to use? Thanks!

snoyes

I think the recommended it every 15,000 miles, but most think that is a little excessive. The recommended type is a GL-5 Synthetic 75W90. All brands in the syn tend to be good, Mopar, RP, Amsoil, etc. Can't remember for the life of me what the stock capacities are since I have the mag Hytecs. Probably around 4.5-5 quarts in the rear, 3 quarts in the front. Hopefully someone will chime in, most likely its in the truck manual as well.

snoyes

And to help answer your question better, if you fill out your signature with your truck information people will be able to better answer your questions. I assumed 3rd Gen, but let us know what you have...

Boss Hoss 540

Just did mine a month ago---used Amsoil in everything from the front dif all the way back to the rear dif.

rich

15k to 20k

Rednecktastic

I did mine at 20K.... Took less fluid than was I was told, it took about 7 qts

RobG

Was that 7 quarts for just the rear, or for both?

I'm probably overdue at 60k... got the truck at 48k and have no idea if they've ever been serviced. I keep telling myself I'll pick up a Mag-Hytec cover for it, then change it, but haven't gotten around to it.

Rob

snoyes

He was talking for both, I'd get 8 just to be sure, but 7 should do it. Make sure to clean your diff off before pulling the covers off, was a post here a little while back about a guy that did not clean his diff off prior to pulling the cover and sand fell into the diff, spent hours cleaning it out. Also, watch the torques on the bolts when putting the covers back on, esp if you get the Mag Hytecs. It was a very small amount of torque required, and have heard of guys snapping the bolts off trying to put the covers back on too tight.

sinawalli

Thanks! I have a 06 3500, 4 door, manual trans, single rear wheel.

Rednecktastic

Yeah go get 8 qts and it has to be synthetic. Reusable gaskets are already there ... Just barely snug the bolts up, it doesn't take much.


I don't care if they say 15K I'm going to let it go 20K each time, just my preference.