I would check the differential fluid. especially if your truck has positratction or some other type of limited slip.  also check the u-bolts which hold the rear springs to the axle.  if the axle slips rearward when the brakes are applied the parking brake cable will tighten the brake on that wheel.  one other possibility is a bad shock especially if the bang occurs on turning. the shock may be sticking up or down and then suddenly releasing.