Popping Sound from rear when backing up

[rbond]

I am looking at purchasing a 1999 7.3 diesel F350 Dually with 50,000 miles. It has a popping sound in the rear wheels when backing up and the steering wheel is turned. Is that the rear end? If so, does it need replacing?--

[twildman]

Originally Posted by rbond

I am looking at purchasing a 1999 7.3 diesel F350 Dually with 50,000 miles. It has a popping sound in the rear wheels when backing up and the steering wheel is turned. Is that the rear end? If so, does it need replacing?--

Sounds like the limited slip differential is popping

[460+]

Same here, sounds like the clutches are binding up.Has the diff been worked on recently?

[StarDriver]

Add some Friction Modifer to the rearend, I'm guessing rear lube was changed and it didn't have any added to it. My Dodge and a 2001 PSD did the same thing when synthetic was put in them.

[HellBilly]

When u-joints start to go out thay start to "Click" when your in reverse.

[pf350]

full lockers will also do this. wouldn't that be a nice suprise to find you had a $600 detroit in there.