I drive a 1998 Jeep Cherokee 4.0 4wd 4.0 and have a terrible loud grinding noise from under the vehicle regardless of how fast or slow I go. Brand new u joint and d rear yolk please hwlp

 

More vehicle info needed

 

Done.. it's a 1998 Jeep Cherokee sport 4.0 4wd

 

Yoke pulled to replace? Was there any significant fluid loss during the work that wasn't replenished?

 

OH! WAIT! You replaced the differential yoke? I'd say whoever installed that yoke overtorqued it and your pinion bearings are grinding themselves up. Working on a differential is not rocket science, but you need knowledge and extreme care when doing it. That nut that holds the yoke on sets the bearing preload on the pinion. Even though that nut needs around 200 lb/ft to turn it, it must not exceed the "torque-to-turn" limits on the pinion gear itself. If you park it now, you may be able to save the gearset before the bearings explode and ruin the entire guts. You can't just loosen it to fix it. You'll have to rebuild the differential with new bearings, shims, and reset the gear lash properly.

OR, get another rear axle assembly.