Rear axle noise

[amwel]

I have 2013 1500 shorty, my 5th one over the last 45 years. It has 12000 miles on it. For the last few weeks I have had a noise, maybe a clunk like something was loose underneath. I took all the stuff out of the back and started unloading the tool box with no luck. If I pulled the wheel back and forth slowly on a flat road I could get the noise just as easily as driving on an uneven road. Went to see my neighbor, a long time mechanic, albeit a Ford guy, and he also looked under the rear but saw nothing. I could replicate the noise by grabbing the bed rail at the rear and shaking the truck back and forth from side to side. He grabbed a jack and put it under a shock mount and lifted one wheel off the ground. Grabbing the tire and pulling out, pushing in, he found the noise and excessive end play. It was more pronounced on the right than the left but there on both sides. The truck has a G80 locking rear end. Yesterday I drove over to the next town, 10 miles and on the way back I realized the noise was gone. I had an appointment scheduled today with the Chevy garage and of course when I went in they found nothing. I did jack up the truck when I got home last night and found no slop so I was not surprised when they looked at me like I had 3 heads. Is there something in this locker that could have caused this as it was not my imagination?

[newdude]

Semi float axle. That is why there is side to side "clunk" if you will. Normal. All that holds the axle in is a metal C clip if you will, there may be a bit of travel as a result.

[barry G]

the short bed will thrash that around for a workout too..

 

check the balljoints up front often.