What diff fluid should I use and how much? Is there a DIY on this?

 

Fluid is up to you. Type is different for the front and back (although I put the same in both). Rear gear oil will be different if there is a limited slip in the rear. Check the manual for suggested weights, I can't remember of the to of my head. I just bought 5 quarts and used it in both axles, ended up with about half a bottle left on the 5th one.

Here is a DIY

http://www.pavementsucks.com/tech-article-4.html

 

Because finding this was so hard:
https://dodgeforum.com/forum/2nd-gen...uid-types.html

 

It was :P

 

Yes, I have LSD, good write-up still a few questions:

1. I have an 01 SPORT OFF-ROAD with LSD, what diff do I have? Dana what?
2. What is friction modifier?
3. Seems like I should buy 75W-140 Synthetic gear lubricant, but how much of it?

 

1. front is d44, probably open. rear is 9.25, probably with LSD.

2. an 8 oz bottle of expensive oil. stocked next to gear oil. the expensive synthetic 75w140 oils will usually include the lsd additive, but i don't think its worth the crazy price per quart.
http://www.amazon.com/CRC-402508-Tra...4980459&sr=8-2

3. you'll need all of 4, probably 4.5 quarts total for front and rear. if you're determined to use synthetic, look for Smitty's Super-S. its about half the price of Mobil and other. here's another reason to reconsider. if you drive through deep water its common to get water in the diff and have to change the oil. its a damn shame to throw out $16 per quart oil....
http://www.amazon.com/Mobil-75W-90-S...=pd_sbs_auto_4

http://www.smittysinc.net/SuperSynGear.htm

 

1. Yes, it does have LSD
2. How much of that additive do I put in?
3. Im going to just do the rears tomorrow, So I need (4) quarts?

How do I know what if (4) quarts is enough, just fill it up to the drain plug in the middle or is that too much? Also, can I buy this additive at Napa and the oil too?