Diff problem?

[sab007]

Hi there,
First timer here. We are desperate to find out if anyone know what could be wrong with our car,Grd Cherokee,auto,4.0ltr. I just love this beast! We bought it at an auction and knew that there would be work on it to be done. There was a drone kind of noise coming from the back end, whining noise. This became slightly worse and suddenly when driving on the motorway something went clonk in the rear back , pulling to the right, once stopped and driving off it was ok again for about a mile. Anyway we were told that it could be the rear diff, so changed the bearings. Since replacing the rear bearings, it was ok until it happened again but now the same noise comes from the front, the diff gets hot and smelly of burning oil. Can it be the front diff which needs replacing or could it something else.

Regards
Sabine