JamesQ

If you can, try getting it onto jack stands after driving and shut it off but put it in neutral and spin the wheels or have someone spin them and see if it makes noise. If it does then you can move around until you find where it’s coming from then investigate further in that area to pin point it. It’s worth a shot. Sent from my iPhone using Tapatalk

What all have you checked? Have you checked all the fluid levels including rear end? It only does it when moving? Is the truck stock? Sent from my iPhone using Tapatalk