Jill Y Plano , TX January 11, 2019 Appliance: Whirlpool 4 1/2 Qt. Stand Mixer Classic - Tilt K45SSAC-0 Whirlpool Mixer K45ssac-0: The higher speed on my mixer was not working. How to replace Speed Control Plate. I replaced both the Speed Governor and the speed Control Plate Do-It-Yourself Rating: Repair Time Estimate: 30-60 minutes