I went to get my oil changed at the stealership and they told me that both of my diff's need to be serviced because they are seaping oil. I asked the service guy to give me a quote and he said $150.00 a piece. I guess he noticed the dumbfounded look on my face and told me that since the XJ is a Chrysler product they have to put in some special additive or something in with the oil that cost a lot of money. Anyone ever hear of this? I've done the work myself on my last vehicle, but before I do it on my XJ I want to be sure it doesn't need the magic solution the service guy says it does. Thanks a lot.

 

Where is the seeping? Do you have Trac-loc, limited slip diff? Which diff do you have D35 or 8.25? 8.25 has a flat lip on the bottom. If you have LSD diff you need the additive if open diff NO. The seeping is at the diff it's pretty normal, due to the plastic plugs. You can do the oil change yourself for less than $30 for both axles, a little silicone on the cover mating surface will seal the seepage. If the seepage is at the axel you need new seal, still easy. With bearings add another $30 to the job.

 

He was trying to snooker ya.
Where are they seeping from if at all ?
I just changed my pinion seal and put in fresh oil in the front diff on mine, I have about $30.00 in it including a tube of ultra black.

 

not sure if I have trac lock or limited slip. It's a 99 Classic, no limited slip or trac lock button inside. Which axle hase the limisted slip the D35 or the 8.25? The seeping is around the pumpkin. It couldn't hurt changing the diff oil, it's just that I don't want to spend $300+ if i don't have to.

 

Both can have it, but more common in the D35. The additive can be purchase at most autoparts stores for less than $10 if I remember correctly. Simple to test for Tracloc, jack up both rear wheels, spin a tire by hand. If the both tire spin in the same direction, Tracloc, you need the Friction Modifier. If the tires spin in opposite directions, Open Diff, NO modifier, just gear oil.

 

i know a guy with a JK they wanted to charge him like $300 at the stealership to change the diffs luckily i was with him and was like NOOOO dont do it ill show you and you can save yourself $250

very simple procedure look for a write-up

 

Thanks guys I figured he was jacking me around. He told me the additive cost like 90 bucks or something like that. I figured he was crazy. What weight oil should I use?

 

heres a good write-up on changing your diff fluid
http://jeephorizons.com/tech/diffoil.html

you should be good with 75w90, i believe thats what i used, i forgot

 

Thanks for that link rweaver, very good write up. Glad I didn't get raped by the stealership!!