Parts for 21AA45M5099 — MTD

We found 68 parts confirmed to fit the MTD 21AA45M5099.

Compatibility table

Prices shown are an informational reference range only, not an offer or an Amazon price — RepairKitHub does not sell parts directly. Each part links to an Amazon search so you can compare current listings yourself.

Common failure areas on this model

The confirmed parts above group into a handful of failure areas. Here is what each points to and how to check it before you order anything.

General hardware and mounting parts

Symptom: A small mechanical or mounting part has failed, cracked, or gone missing.

Check: Compare the physical shape and mounting points to the original piece, and confirm the exact part number against your model plate before ordering.

Parts in this group on 21AA45M5099: 777S33382 (Label), 777I23106 (Tiller Decal), 777I20451 (Label-gear/t), 777S33508 (Kmart Tiller Decal), 78601810691 (Tiller Shaft Rod Lever), 6860109A (Crank Assembly), 6170058A (GEAR ASM-REV), 6170062A (Gear Assembly), 7311595 (Ryobi Counter Weig), 7260277 (Ryobi Plug-taper C), 7380645 (Ryobi Shaft), 7171584 (Ryobi Spur Gear), 7410421 (Tiller Bearing), 9410420 (Tiller Bearing), 7461117 (Tiller Clutch Cable), 6110128 (Tiller Shaft Assembly), 6170060A (Tiller Tine Input Sprocket Assembly), 9130484 (Tiller Tine Shaft Drive Chain), 7471219A (BAIL-CLUTCH), 73804424A (Jackshaft), 777I23259 (Label), 7200313 (Ryobi Grip), 6110129 (Ryobi Tiller Input Shaft), 7471152 (Ryobi Tiller Shift Rod), 7111349A (Tiller Input Shaft), 6170061 (Ryobi Sprocket Assembly), 9461117 (Tiller Control Cable), 9410600 (MTD Lawn Tractor Ball Bearing).

Drive system (belts, pulleys, motors)

Symptom: A drum or tub that won't turn, a burning-rubber smell, or a loud thump or squeal during a cycle.

Check: With power off, turn the drum or tub by hand -- resistance or grinding points to the motor or a bearing, and a cracked, glazed, or snapped belt is visible once the cabinet is open.

Parts in this group on 21AA45M5099: 7840158B0709 (Belt Cover), 7840158B0691 (MTD Tiller Belt Guard), 7840158A0662 (Belt Cover), 78601930637 (Idler Keeper), 7171582B (MTD Tiller Gear Case Shaft Spur Gear, 44-Tooth), 7860064A (Ryobi Idler Bracket), 7471159 (Ryobi Rod Idler Pulley), 7171585 (Ryobi Tiller Gear Case Shaft Spur Gear), 7171594 (Ryobi Tiller Gear Case Shaft Spur Gear, 16-tooth), 7171587 (Ryobi Tiller Gear Case Shaft Spur Gear, 44-tooth), 7171583 (Ryobi Tiller Gear Case Shaft Spur Gear), 686041290637 (Tiller Gear Case Cover, Left), 6170059B (Tiller Idler Pulley), 7561162 (Ryobi Tiller Input Pulley), 61104074A (Tiller Gear Case Wheel Shaft).

Storage, trim and cosmetic hardware

Symptom: A cracked shelf, broken door bin, worn hinge, or missing trim piece -- cosmetic and storage wear rather than a functional breakdown.

Check: Match the physical dimensions and mounting tabs of the old part before ordering; these pieces are often model-specific even between visually similar models.

Parts in this group on 21AA45M5099: 7860185A0637 (Bracket), 78601770691 (Bracket-lh H), 78601760691 (Bracket-rh H), 6490041B0691 (HANDLE ASM-U), 7100506 (MTD Lawn & Garden Equipment Hex Screw), 7840208D0691 (Shift Cover), 6860044B0691 (Tiller Side Cover), 64900340691 (Tube Handle Assembly), 7500194 (Kmart Spacer), 78601870637 (Shift Bracket), 9380958 (Shoulder Spacer), 68601110637 (Tiller Bracket Assembly), 7860090A0691 (Tiller Side Shield), 7860178A0691 (Tine Shield), 7860238A (Craftsman Bracket), 7100946 (Ryobi Lawn & Garden Equipment Truss Head Machine Screw), 78601800637 (Shield Bracket).

Before you buy

Match 21AA45M5099 exactly against the model and serial plate on the appliance itself before ordering anything — a single mismatched character can point to a different production run with different parts. Then check the part number printed or stamped on the part you are replacing against the part numbers in the table above; the printed number is the most reliable way to confirm fitment when a model has gone through multiple production runs. RepairKitHub does not sell parts directly — every part link above routes to an Amazon search for that part number so you can compare current listings and sellers yourself.

How to confirm this is your model

Check inside a door opening, on a back or side panel, or behind a removable panel or drawer for a label printed with the model and serial number. Match every character exactly, including letters and dashes at the end — appliance model numbers often have similar prefixes but different suffixes for different production runs.

Still not sure?

Use the model lookup tool to search by model or part number, or start from the symptom your appliance is showing.