When I am in a stopped position and turn left or right the rear end seems to make a sound as if something is grinding.I have also seen this if i pull up my slightly inclined drive way.

Dear mark32-- From the little you tell me I would guess that the problem may be in the differential- either the fluid or a bearing. But, it might be in the U-joint. I suggest you take an honest mechanic for a short ride and let him have a listen. Good luck from Bovan.

Is this the AWD model? If so it could be the traction system engaging automatically. IOf not, it could be the differential engaging in refernce to your wheel turning, as the wheels become slightly unbalanced. If it persists, have the differential fluid checked, along with a check to see if there is any significant metal particle inclusion in the fluid, which could indicate excessive wear.

If the ideas listed haven't panned out,check your spring hangers.States with bad winter roads,(where they use a lot of salt and saw dust) are notorious for underbody rot and the spring hangers get more than their share.I don't buy from neighboring states because of this. I had a ford explorer that had undercoating sprayed on them to hide the rot.I'm glad I found it in time!

have your breaks checked or you have a bad bearing

So you're not moving forward, & you are turning the steering wheel left or right? If so, the noise isn't coming from the rear of the truck, but from the power steering pump in the engine bay, & may need to be replaced if worn out.

This sounds like what mine is doing also, except, I called it a washboard sound. I suspect either the rear end or the universal joints. I serviced my rear end and changed my universal joint at 125K. The sound subsided but now that I'm at 255K it is back really bad. I guess I need to bite the bullet and do both again. I hope someone knowledgeable knows what to reccommend.