Front and rear Diff's take the same fluid, however do you have a "locker" or traction control devise in the rear? If so this will require a friction modification fluid. Jeep has there own but you can use different types if there available in your area. Friction modifiers keep the clutches in the "locker" lubricated, cool, and funtioning. If you don't know post the tag numbers off the rear end or fron end and I can tell you.Some will actually have two takes and one will state that you have a limited slip diff.