"Clunk" when accelerating

Hello any help would be appreciated. I bought this truck about 6 months ago and it had the noise a little now it has gotten to the point that you can hear it clearly. When I accelerate away from a stop sign weather fast or slow I hear a "clunk" come from the rear end. I live in alaska and it gets to -60° so I figured that it was just the truck making noise because I bought it when it was -20° out. It is now in the 70's and it is still there. Does anybody have any idea's i.e. axle wrap, loose rear end, shocks...

Thanks,
Tyler

a broken mount somewhere.

A "clunk" is the classic noise made by a worn universal joint. Have them checked.
Mark

thanks a lot, ill check both