So my fiancé and I both bought Xj's about a month ago I today in the snow we have had I noticed that all four wheels spin on hers in PT and hers has the Dana's front and rear, and mine has the Chrysler rear and the Dana in the front and only one rear wheel spins and one front wheel.. It doesn't make a whole lot of sense to me. Maybe some explanations? Thanks guys in advance I'm Zak by the way.

 

Her Cherokee has either Limited slip Differentials or Lockers in both Differentials, and yours are both open.
Open meaning that power will go to the wheel with the least traction, that is
why we put lockers and LSD in our rigs for use on trails.

 

A google search on how a differential works is going to be the most helpful to you right now.

 

Ok, I figured that the Chrysler rear end would have been the better one. So is there a cheap or easy way to make mine that way? Mine is more of a play jeep, hers is all stock that we are going to use in the winter and she has a cobalt ss to drive in the summer. Haha. But I would like mine to have the ACTUAL 4X4. Haha.

 

Most 4X4 vehicles perform just like yours. Read up on traction enhanced diffs. About $250 up and 2 hours of your time will get a auto locker (lunch box locker) for the rear. With a rear auto locker, u may never use 4WD again.

 

Is it possible that mine has a posi unit but the clutches are worn? It does have 280,000 miles on it.

 

Yep, that's possible. If you get your vin# build sheet from Chrysler it will tell you whether you have the limited slip in the rear... although, in many conditions even a good limited slip will allow still allow only one wheel to spin.

 

Jack one wheel up, in neutral, brake off.......can u easily turn the wheel by hand? If yes, either the diff is open or the clutches are totally shot. Have u serviced the diffs?......with the covers off, it's easy to tell open from limited slip.

 

No I haven't serviced it yet. I'm waiting for warmer weather. Haha. It needs an oil pump too.