I would venture to say the shaft has its own o-ring in there some where. But any gritty water that gets in the shifter will stay and ware on that o-ring.
Thanks Mark, but than what about the little electric shift motor...there is nothing there either...if this is true, I would imagine it having a similar issue, right?
Mark, I went back and watch him take the motor off the Tcase and if you look, the shaft that's coming out is surrounded by a ridge which I would imagine sits flush with the electric motor and the shifter......but even so, can't imagine it being water proof....did you watch it? What do you think? What happens if the entire Tcase or the truck is completely submerged?