Two problems related to transmission gear slipping have been reported for the 1999 GMC Yukon. The most recently reported issues are listed below.
While driving at 60 mph rmps revved up, and the transmission slipped, mechanic inspected the vehicle, and indicated that the transmission malfunctioned due to a failure in the ball valve. Also indicated that this was a common problem with these vehicles, and this part has been up graded in later model years to correct this failure.
Basically consumer was having a problem with abs braking system. When applying brake pedal, pedal stuck and ruined rotors. Also, air conditioning went out three times due to a hole inside of vent area. Check engine light came on due to faulty harness. Transmission slips on acceleration. The engine runs rough at idle. Button on left front seat rattles. Right front outer brake pad was worn. Vehicle pulls left when applying brake.