2004 GMC Yukon Speedometer

2004 GMC Yukon XL, 60,000 miles, 5.3 V8, auto, 4X4. Speedometer on occasion while driving on the highway, begins to climb until it reads past 120 mph, and sticks. After some small slow trips it works its way down and begins to work correctly. When malfunctions occur, it is during highway travel.