I also have a leak on the shaft....but not the kick down. The kickdown o-ring is good and sealing. The metal clad seal that surrounds the Manual Control Lever going through the side of the case is the one that is leaking. I had the trans rebuilt and only have a few hundred miles on it. But, unfortunately the (shady) shop that rebuilt it didn't give me a good waranty. I have replaced the metal clad seal in the side of the case twice. The shaft has been checked for wear and is in really good shape. No grooves at all. Is there something I am missing? It is frustrating because it is all that is wrong with the truck. I have alot of money into it. With the leak it only goes down a quart but I don't want to burn up the clutches. Sorry to ramble. If anyone can give me some insight as to what the problem is I would be very greatful. Thanks.