Inspect the differential for cracks. If there are none, it is probably coming from the cover gasket. Drain the differential and remove the cover. Put a new gasket on (be sure to use gasket sealer). Then refill the differential with the correct fluid.
It will depend on what type of leak it is. Inspect the differential for cracks. If there are none, it is probably coming from the cover gasket. Drain the differential and remove the cover. Put a new gasket on (be sure to use gasket sealer). Then refill the differential with the correct fluid.
Typically a leak is simply caused by a bad seal that has hardened or got damaged. You need to get under the vehicle and locate which of the seal has the problem. Once you figure out which one it is then you can buy a new one and install it into the axle housing.
It will depend on what type of leak it is. Make sure the third member is not. If it it the seal just replace it or use a thin coat of gasket replacement sealant. Then make sure to tighten to the manufacture spec or it will cause a leak again.
You will first need to locate where the leak is on your Jeep Cherokee. Once you find the leak you can fix it by inserting a sealing type material on the hole.