Looks like the bearings on the back of my differential case where the drive shaft connects is bad, you can wiggle the drive shaft around. How hard is it to replace it? I have heard there are some specific specs and if you get them off just a little bit you can really mess up the rest of the vehicle. My b/f and bro in law work on cars often but don't deal too much with differentials or transmissions.. What do you think? Also if it is difficult, what is the cheapest way to fix it, buying a used axle or trying to find just the diff. case with gears already intact? PLEASE HELP!

 

The CHEAPEST way is to replace the bearings, but that takes experience and finesse to do it right. That is as long as the ring and pinion are still good.

The EASYIST way it to replace the axle assembly with another one. Make sure the ratio is the same as what's in there now. The diff case doesn't come apart, like a Ford.

DO NOT DRIVE IT any more than you have to or it will grenade! Been there, done it, have the t-shirt.

 

I have quit driving it...it's on stands right now ripped apart as we were trying to make sure if was the diff. It was making a loud grinding and then popping noise coming from the front end, when I stopped driving it. I was told there should be some code stamped on it that I should match to the new axle, guess that has something to do with the ratio?

 

if the pinion gear has that much slop in it the gears are toast. Is it All wheel drive? I see that a lot when the tires are mismatched front to rear on AWD vehicles. The front diff gets cooked. As stated above if you are not familiar with diffs they can be very particular in their set up and it may be cheaper & easier to swap the whole thing.

Miles

 

There is a tag mounted under two bolts on the cover. That will have the ratio stamped on it, If it isn't there, check the rear. If that isn't there, pull the cover and count teeth. Ring divided by pinion = ratio.

USUALLY, it's 3.55 or it's 3.73 with the tow package. I say usually because it can be built any way the original purchaser wanted it.

 

It is AWD

 

Check that all tires are same brand, size, model & have the same amount of tread left or you may be right back in the same situation after fixing the front diff. Always change all 4 tires at the same time never just change 2 with an AWD.

Miles

 

If you have mismatched tires, it will also destroy the viscous clutch in the NP249 transfer case.

 

Found it on the front diff. case. Looks like I have a 3.73
Thanks for all your help everyone! Now the search begins!

 

If you find one in a local yard, pull the cover and inspect the gears before you buy it, or tell the guy you'll bring it back if it's bad. Definitely inspect it before pulling yours out. You don't want to put a bad axle in your jeep, only to pull it out again. WAY too much work!