One problem related to wheel bolts has been reported for the 1999 GMC Yukon. The most recently reported issues are listed below.
While getting a new set of tires on my 1999 GMC Yukon, 58000 miles, the lug nuts on the right front and left front wheels would not tighten. The mechanic was using a torque wrench to tighten the lugs. Four lugs on the left front and two lugs on the right front began to stress and to kneck down. I instructed the mechanic to cease and to remove the wheels from the vehicle. There was definite evidence of knecking and the lugs appeare to be very malleble. I had the lugs replaced with new lugs, and retained the lugs that were removed from the vehicle. I am a structural engineer and in my mid 60's. I have never seen the quantity of lugs from one wheel be so soft. I am the second owner of the vehicle and have been driving it since the last week of June, 2005. I believe the tires that I replaced were original equipment and this was the first time that they were off the vehicle. I believe that the Yukon was manufactured in wisconsin.