One problem related to engine knocking noise has been reported for the 2001 GMC Yukon. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2001 GMC Yukon based on all problems reported for the 2001 Yukon.
When vehicle is cold engine makes a knocking noise and is sluggish. Duration of the problem has progressed currently affecting vehicle when it warms up. Dealer was contacted and was aware of problem. Consumer states the engine has piston problems.