Michael P Saint Louis , MO December 15, 2014 Appliance: KitchenAid 5 Qt. Stand Mixer Professional Heavy Duty Bowl Lift KG25H7XOB5 Kitchenaid Mixer Kg25h7xob5: Kitchenaid mixer was slipping gears. How to replace Transmission Housing. I make a lot of bread doughs with my KitchenAid mixer, and it's used 2-3 times a week for large batches of dough. The gears began slipping, and I decided to take the mixer apart, and replace the worn gears. Replacing the transmission housings plastic cover, with the newer metal one will probably result in me not having to repeat this process, as the plastic one broke at the screw holes under pressure. I also replaced the worm gear, and the sleeve bearings. 16 People found this story helpful Do-It-Yourself Rating: Repair Time Estimate: Less than 15 minutes