Diesel 2500 when we come to a complete stop there is a delayed clunk in the rear of the truck. Sometimes when we take off it does it too. Just had new rotors and brakes replaced in the rear thinking that was the problem. Any suggestions?

The problem is in the axle and differential. THe clunk or kick in the **** you feel is the axle spinning down at stop. The gears are what is making the clunking noise. When you release the brake and begin to accelerate teh gears have free play in them and the clunk then is when the two gears actually make contact. You might notice that when you first start your acceleration there is not an immediate response. Meaning the RPM's go up a tad before you actually start to move. Check the lubrication in the axle shaft and the differential. You can do this through a screw hole (plug) located on the differential. Its called the finger test. Stick in your pinky and it shoudl come back covered in grease adn oil. (please do this with vehicle off and on level ground, etc BE SAFE) If possible it should really have the differential cover removed and checked for metal shavings indicating abnormal gear wear or adjustment. If you are not a handy mechanic or have the ability to do this with the truck on a rack, its best handled by a qualified service location. You didnt indicate the manufacturer, but GM's are famous for this and some Fords are too.. but GM's more so. Good luck. P.S. if it were the brakes you would hear the clunk when you applied them but not when you released them.