KitchenAid Stand Mixer Worm Gear Parts — Models & Compatibility

Your KitchenAid mixer motor is running but the attachments won't turn? That grinding noise you're hearing is often the worm gear — a plastic sacrificial component designed to strip before the motor burns out. This hub covers W10112253 worm gear compatibility across KitchenAid tilt-head and bowl-lift stand mixers, including the popular Artisan and Classic series.

Is This the Right Part for Your Model?

The W10112253 worm gear fits most KitchenAid 4.5-quart, 5-quart, and 6-quart stand mixers. Your model number is stamped on the bottom of the mixer base — flip it over and look for the format like KSM150PSMH0 or 3K45SS. Cross-reference with the compatible models list below. This part replaces older numbers WPW10112253, 4162897, 4161531, and 4169830.

About This Replacement Part

The worm gear is intentionally made from plastic to act as a failure point when your mixer gets overloaded. Heavy bread dough, jammed beaters, or running the mixer too long can strip the teeth on this gear. When it fails, the motor keeps running but the planetary head stops rotating — you'll hear the motor whirring while the dough hook sits motionless. One owner described it perfectly: "After a 10 min bread dough knead with the hook attachment, the hook stopped spinning, but I could hear the motor continuing to try."

This is a moderate-difficulty repair that takes 30-60 minutes. The trickiest part isn't the gear itself — it's getting the retaining pin out that locks the gear to the shaft. You'll need a good punch and hammer, plus patience to drive that pin without damaging the housing. One installer noted: "Hard part is to remove the pin locks the gear. Need to have good tool to hammer the pin out." Don't skip the grease replacement step — remove all the old contaminated grease and pack the new gear with food-grade grease to prevent debris from grinding back into the gearbox.

Common Symptoms This Part Fixes

• Motor runs but mixer does not turn
• Dough hooks will not rotate
• Planetary head no longer rotates
• Grinding or clicking noise from gearbox
• Mixer won't turn unless you help it manually

What You'll Need for Installation

Basic tools required: Phillips and flathead screwdrivers, pliers, socket set (typically 9/16"), pin punch, and rubber mallet. You'll also need food-grade grease (Benalene 930-2 is OEM-spec). Plan for about 45 minutes if this is your first time. The YouTube videos from repair parts suppliers walk through the disassembly step-by-step — watch one before starting so you understand the pin removal technique.

Why This Part Fails

Heavy loads cause 90% of worm gear failures. Bread dough with more than 4 cups of flour, sticky cookie dough, or running the mixer continuously for over 10 minutes generates enough torque to shear the plastic teeth. Foreign objects jamming the beater also cause instant failure — as one customer admitted: "Our mixer stopped operating due to the blade getting jammed on an item that should not have been in the mixing bowl. All my fault." The good news? Replacing this $15 part beats buying a new $400 mixer.

Installation Tips from Real Repairs

Before you start, unplug the mixer and flip it upside down on a towel. The bottom panel comes off with four screws. The motor housing separates next — this is where things get tight. The cord strain relief is notoriously difficult to remove and reinstall. One tech advised: "Hardest part was getting the cord strain relief out/in from the housing." Once you're inside, you'll see why the pin is so stubborn — it's pressed in, not threaded. Tap it from the non-threaded end with a punch that's smaller than the pin diameter. Sand the pin lightly before reinstalling to help it seat properly.

When reassembling, don't overtighten the motor housing bolts — you're threading into plastic. Snug is enough. Test the mixer at low speed before putting the head back on to verify the new gear meshes correctly. If you hear clicking or resistance, the gear isn't seated fully on the shaft.

Compatible KitchenAid Stand Mixer Models

This W10112253 worm gear fits the following KitchenAid stand mixer series and models:

This is a partial list — over 200 KitchenAid models use this worm gear. Verify your specific model number before ordering.

Frequently Asked Questions

How do I know if it's the worm gear or something else?

If your motor runs but the attachments don't turn, it's usually the worm gear. If nothing happens when you turn it on — no motor sound, no lights — check the speed control board first. You'll need to open the mixer to visually confirm the gear is stripped.

Can I use regular grease instead of food-grade?

No. The gearbox is part of your food preparation equipment, and grease can migrate onto food contact surfaces. Use only food-grade grease rated for high-load applications. Benalene 930-2 is what KitchenAid uses at the factory.

Do I need to replace the center gear at the same time?

Not always, but inspect it. The center gear (drive gear) takes similar abuse. If its teeth show wear or chipping, replace it now while you're inside the mixer. There's a pin through the center shaft holding it — this is the second-hardest part of the repair after the worm gear pin.

Will this gear fit my 7-quart Professional model?

Check your model number. Most 7-quart bowl-lift mixers use this gear, but some Pro Line models use a different gearbox assembly. The model tag will confirm compatibility.