When I'm towing with my 2001 every time I go over a frost heave or bump I think my TC lets go because my RPM goes up about 200-300 and stays there, Especially when going up hill, the truck falls on its face when it "Unlocks". What could be the problem,the truck has 250,000miles and an Edge EZ. I don't know if that makes sence but thats the best i can describe it.