96 gmc problem

i have a 96 z71 with the 350 vortec motor well driving the truck will surge and make a loud clung from the rear end. i have maybe 1000 miles on a remanufactered motor and i had the tranny rebuilt about 2 years ago. also the rear brakes seem to stay engaged on one side. i have replaced the brake shoes and all the hardware with new and it still has the problem.any help with this would be great.