The trouble started the minute we started pulling the jet skis to the water. The dealer had been "towing his bass boat without a problem" for a month. The vehicle had problems staying up to highway speed on any inclination. For statement of fact, I was towing two (2) Polaris 750 jet skis. A lot of the trips were 200 miles to the coast and back home.
The first transmission the vehicle wasted was about 750 miles. Since purchasing the vehicle I have had 9 replacement transmissions from the dealer and 2 rebuilds. The truck current will not shift gears appropriately and needs a new rebuild or replacement.
I have tried adding an additional coolant system for the transmission to no avail. After the first transmission, I did pickup up on the transmission deposit on the back window of the truck. I believe this is from the overflow vent on the passenger side of the transmission leaking onto the exhaust.
The original engine has been rebuilt three (3) times and head gaskets replaced once since the last rebuild.
I have had the same problem with the anti-lock brakes as I have read in other reviews. After approximately, 2 years of ownership the problem resolved during a recall on the brake system.
I still have the vehicle because I rarely sell any vehicle I have owned. This is my distant 4th or 5th vehicle and not my principal. I am considering a complete re-engineering of the drive train, since I have still used the vehicle for hunting.
General motors and the dealer were no help what so ever. I don't think they have a clue. The GMC Jimmy is a LEMON and an engineering failure.
I would never own another General Motors product.
Shouldn't be towing 2 750 jet skis with a v6 SUV man. That's the reason for your 9 trannys, not GM.
Note: A Comments RSS Feed 
is available. New comments appear in the Members Area before the main site