This page contains resources useful for anyone who is preparing to do maintenance or overhaul on any full-sized tilt-head or bowl-lift model which has a round rear cover secured at the top with a screw.
Models included: the original Model “K”, K4-B, K45, K45SS, “Classic”, “Classic Plus”, “Artisan”, “Ultra Power”, and all similar machines except the Accolade and Artisan Mini; as well as the older bowl-lift machines in the K5 series: K5A, K4SS, K5SS, KSM5, KPM5, KSM50, KSMC50S, KSM450, KSM500 and all similar. Note that this does not include the vintage 4C/3C/3B models.
If you are going to DIY this job, you will need the following items:
- Gear case gasket: part #WP4162324 (see note below)
- Center shaft O-ring: part #WP67500-55 (see note below)
- Planetary retaining pin: part #WP9705443 (5/32 x 7/8″ type-E grooved drive pin)
- Grease (6 fl-oz, NSF H-1/ISO 21469 rated for food safety, NLGI #2 viscosity, see below)
About the gear case gasket: Beginning in late 2025, WP4162324 was superseded by W11805888, which by all appearances is the same part at more than twice the price. Depending on the source, the old part number may be listed as “discontinued” or “no longer available”; or the old part number may be listed at the new price. If you are very lucky, you may be able to find the old part at the old price (around US$10-15).
As an affordable alternative, Goodman’s sells an aftermarket gasket which is of good quality and is a suitable replacement, and it is very inexpensive. You can find it here or by searching for either of the above part numbers on their web site.
If you are repairing a failed or heavily worn “sacrificial” gear, you will need these additional parts:
- Worm follower gear, part #WPW10112253 (see important note below)
- Pinion drive pin, part #WP9705444 (3/32 x 3/4″ type-E grooved drive pin)
Important note about the gear: do not buy the cheap aftermarket gears that you can get on Amazon. They are not built to factory specifications and will fail, sometimes immediately. Always use the genuine part. Read more on why.
Here is a video which shows how to replace the “sacrificial” gear. It’s also a good general guide for getting into this type of mixer, even if you’re only doing routine maintenance and don’t need to replace the gear.
Another important note: If you are repairing an older mixer, it is worth the effort to replace only the gear, rather than the entire drive assembly. Not only is the part less expensive, the drive bearing is of much higher quality than the replacement part. You can read more about that here.
The O-ring is a standard item which you can probably find in most hardware stores: 1/2in OD, 3/8in ID, 1/16in CS. The pins are commodity parts as well but may be harder to find, so it’s often simpler to order them as repair parts.
Repair part number 4160474 is a rebuild kit which includes a replacement center shaft, center shaft pin, planetary retaining pin, O-ring, and gasket. This is ideal for older mixers.
If the speed control lever is bent or missing its knob, you can replace it while the mixer is open. The repair part number for the lever with the black knob is WP9709276; for the gray knob is WP9709277; and for the “buff”/tan-colored knob is 3184195.
Here is a video which shows how to replace the speed control lever. It’s also a good general guide for getting into this type of mixer.
Likewise if the tilt latch lever is bent or missing its knob, the repair part number is WP24452 for the entire latch assembly with a black knob.
Grease Recommendations
The factory service manual specifies 6 fluid ounces (about 3/4 cup) of grease. Mixers produced after around 2020 or so have been using much less, to the detriment of performance and reliability.
The grease must be NLGI #2 viscosity, and NSF H1 or ISO 21469 rated for food safety. I like the Super Lube 41160 (one 14oz can is enough for more than two mixers); you can buy it on Amazon. Valid alternatives are Mobil FM222, Phillips P66 Food Machinery Grease, CRC SL35600, and CRC SL35610.
If the greases mentioned here aren’t available, any reputable name brand that meets the requirements will suffice. I recommend avoiding anonymous “white label”, repackaged, or otherwise unidentified grease.
Parts sources:
- Appliance Parts Pros
- Repair Clinic
- Reliable Parts (US)
- Reliable Parts (Canada)
- Sears Parts Direct
- Seneca River Trading
- Goodman’s
Tips and Tricks
Work on the mixer upside down. When starting the job, first remove the rear cover, trim band, and planetary drip ring while the mixer is upright. Then, invert the mixer into a supportive cradle (use a towel to protect the finish) or have a helper support the machine. On a tilt-head model, loosen the hinge pin set screw and use a punch to drive out the hinge pin, and lift off the pedestal base. On a K5 machine, remove the four large screws at the top of the bowl column and lift away the base assembly. You’ll have much better access to the internals, and it’s much easier than trying to wrestle around a heavy motor and upper housing during disassembly and reassembly.
Clean out all the old grease. Every bit of it. A tongue depressor or similar flat crafting stick is effective for taking out large globs of old grease. A toothpick or a dental cement spatula is good for getting grease out of tight spaces such as gear teeth, and you can wrap a soft cloth around it to get into the corners of the upper gear case. You can use a light solvent such as mineral spirits or an aqueous degreaser to clean the metal parts. (Brake parts cleaner is very fast but very expensive.)
Wipe out the inside of the gear case and lower housing using a soft cloth and isopropyl alcohol. This will ensure that all of the old grease and wear products are removed, and there isn’t enough old grease left behind to cause any compatibility issues with the new grease.
If you have (or have access to) a parts washer or large ultrasonic cleaner, these can be huge time savers.
Always replace the groove pins, gasket, and O-ring. These are consumable maintenance parts. Reusing a groove pin (from the planetary or pinion drive) creates a risk that the pin will come out of place while the mixer is running. A used gasket or O-ring will allow leaking of grease and/or separated oil out of the gear case.
Keep track of the fiber washers. The center shaft (drive shaft) has a minimum of two washers on it: one is under the main gear, and the other is above the planetary. There may be more than one in either location. When disassembling the mixer, keep careful track of where the washers were, and put them back in the same locations they came from. If you lose track of where the washers go, examine each one closely. If there are only two washers, one of them will have a ring indented around the center hole; this one goes above the planetary. If there are three, then two of them may have these indentations, and if so both of them go above the planetary.
Watch a couple of videos. Some steps during reassembly can be a little tricky, such as joining the case halves, getting the planetary shaft holes to line up so that you can insert the pin, and setting the drip ring on. Here’s a YouTube playlist with some short videos, each of which shows a different part of the assembly process.
Updated: 1/7/2026