One problem related to steering rack has been reported for the 2002 GMC Envoy. The most recently reported issues are listed below.
Power steering rack failed at highway speeds, making it difficult to steer vehicle. Dealer has inspected vehicle and determined that steering rack would need to be replaced. There was a loud noise due to no fluid in the power steering reservoir. Rear differential leaks. Driver side front and rear doors rattle and flew over large bumps. Interior courtesy lights do not come on when passenger side door is open.