Anyone having issues with cruise control speed variation? My 2019 Yukon Denali cruise control cannot maintain consistent speed - currently 5,300 miles and problem has existed since new. Speed variation is a 6 to 7 mph swing: 3 or 4 mph below set speed to 3 mph above set speed. Variation occurs at all speed settings, on flat roads and minor hills. Dealer tells me nothing is wrong with SUV or cruise control. Dealer loaner vehicle, 2020 Acadia, maintained cruise control speed withing 1 mph. It seems an $80,000 SUV would have a better cruise control.