I have a constant grinding sound (metal rubbing) when I go over about 25 or so. The sound is constant does not change or stop when I break, turn, or let on or off the gas pedal. I just changed all my breaks because I thought it might have been them rubbing. So I know I have a bunch of probs with my drive train but I'm not sure how much. Ok, so I jacked the back of the truck up and rotated the tires the rear shaft did not spin is it supposed to? When I turn the wheels I did not replicate the sound. Second the front and rear shaft have play, if I try to twist by hand there is about a 1/4 inch of play in the rear and its a bit worse in the front. I know i'm prob missing some info need so please get me started her....Thanks!

 

Where is the sound originating from? Front, back, left, right? Does it increase with speed?
While you were under there did you check the u-jounts? If they are super toasted they can cause a metal on metal sound.
Stick a screwdriver in the u-joints and pry them around. Look for slop between the cap and main body of them. Your other comments sound normal.

 

Here's what I found....There is no play in the U-joint it self, just the entire shaft. So thats a good thing. The truck I bought I have found mud in every nook and cranny of this truck so I thinking it was ran thru some heavy stuff at one point. I am going to lube everything up and see if that helps any. I know I will need to u-joints soon I am sure. The wheels also have some play so I suppose it could be a wheel bearing also.

 

Check the front wheel bearings?