Recently had the same thing happen to us and it scared the bejesus out of us! Our dealer explained to us that if the jack is overextended to the point of making a popping noise a little keeper pin will break and the majority of the time, that is how it happens. Ours was an easy fix Our T/C sits on a 4x4 heavy duty Dodge CTD so to clear everything when putting it on and taking it off I probably took the front two jacks a little too far. When off the truck at home the jacks sit on a set of cinder blocks so they don't have to travel as far.
