I just got my car put back together with much trouble and expense. Drove the car for the first time in 3 1/2 yrs, new rear end is only 3 weeks old. When driving, I let off the gas and get shuttering or binding up feeling in the rear end and the tires want to try to lock up. My brother jacked up the rear of the car, spun the tires in the forward direction and they would turn fine for a short period of time, then would bind up. He would turn them backwards and everything seemed fine. He would turn them forward again and they would turn for a short while then bind up again. He then disconnected the driveline, did the same thing and everything seems just fine. Could it be the driveline (U-joints) or could it be something worse. He doesnt know either. Any help is severely needed, supposed to take into shop for new ragtop tomorrow!! Help is greatly appreciated! Thanks!