Bob, post this in the Engine and Driveline Shop


If I were to take a guess, this problem is why the last owner parked it. Check your u-joints. Did you grease them? If I remember correctly this truck has not been driven in over 15 years. All you are hearing is a popping sound is that correct? No howling of the rear end or transmission? How does it shift? No binding in the shifting? The transmission stays in gear when you drive it? Confirm these questions and then post again in the Engine and Driveline Shop.