My 89 Blazer has a horrible noise that we can't quite isolate. The conditions are: interstate speeds (70 or so) for 10 or more minutes. After I slow down/stop and start to take off again there is a horrible sound like maybe something in the driveline is binding for a spilt second and releasing creating a loud metal clunking noise. It happens a few times after going again then stops. It never happens when driving in town. I have had the transfer case, transmission, and rear end looked at be a local shop with no hint of problem. I pulled the front diff cover off tonite and it looks good as well. Clean oil, no metal flakes. I can only conclude that the hubs are somehow "catching" as they get hot(they do get hot, is this normal?) They are the stock hubs. I have 254,000 miles on the truck...everything is original except the engine which I swapped out 10 months ago. Sorry for the long post but this should cause one of you guys to sayh yeah...been there done that!! 1989 K Blazer Warn M12000/Enforcer Bumper 32's 254,000 Miles and still going!!