Just purchased a 2001 auto extended cab 4x4 off road package.When I give it gas to take off a noise like clunk and the feeling like the whole drive train is lifting. I have check the mounts and all are good. I had one mechanic look at,his answer possible leaf springs. Any help would be appreciated. Thank you John

 

check your rear axle u-bolts they could be loose

also could be the transmission mount ( broken , worn-out )

 

mine was i had the take the rear driveshaft out and put some bearing grease in the slipyolk..this is if your driveshaft is the steel 2 piece...