2013 2500 Diesel 4x4 150,000 kms, I noticed the other night on highway , I was cruising at 100 kmh and took my foot off throttle for a few seconds than resumed speed. there was a clunk come from rear diff. I released throttle again and resumed and the same clunk. My wife was with me and she said whats the noise from. I put in 4wd and tried again and there was no clunk noise when i tried again. I put back in 2wd and the noise was there upon deceleration and acceleration.. It almost makes me think that the cross pin in diff is loose. Has there been any problems with this with anyone else, I tried my 2001 2500 today with 660,000 kms and there is no clunk when i try the same acceleration deceleration .

 

Dealer checked out today and everything is good underneath truck. Called it a ""power train wind up noise"". under acceleration. guess i will use it that way..