Electric PTO Clutch for John Deere LX172 LX173 LX176 LX178 LX188 Replacement Part Number AM100979 AM115090 AM118969 AM122969 5215-35

What It Is

This electric PTO (power take-off) clutch engages and disengages the mower deck blades on select John Deere LX series lawn tractors. It replaces OEM part numbers AM100979, AM115090, AM118969, and AM122969.

Fitment & Compatibility

Direct fit for: John Deere LX172, LX173, LX176, LX178, and LX188 models with 38” to 48” decks.
Check before buying:

• Confirm your mower’s deck size – this clutch works with all factory decks on these LX models, but verify pulley diameter (typically 3.5” or 4.0”).
• Measure the mounting bolt pattern – should be 2.75” center-to-center (three-hole pattern).
• Ensure your PTO wiring harness has a standard two-pin connector (not a three-pin or oddball plug).
• This is an aftermarket replacement, not OEM. It may use different bearings or slightly different wire colors – compare to your original clutch before installation.

Key Things to Know

• Installation difficulty: Moderate. Requires basic hand tools (socket set, screwdrivers) and ability to access the clutch under the engine. Expect 1–2 hours.
• Common gotcha: The air gap between the clutch rotor and armature must be set to 0.010–0.015” after installation. Use a feeler gauge – too tight or too loose causes slippage or failure.
• Quality note: At 4.2 stars (13 reviews), this is a budget alternative to OEM ($200+). Some users report shorter lifespan (2–3 seasons vs. 4–5 for OEM). Inspect the bearing for smoothness before installing.
• Wiring tip: The aftermarket clutch may have black/white wires instead of OEM’s red/black. Swap connectors if needed, but polarity doesn’t matter for this clutch – just a clean connection.

Should You Buy It

If you need a quick, affordable fix for a failing PTO clutch on an older LX series mower and don’t mind a slightly shorter service life, this is a solid choice. It’s best for DIYers comfortable with basic mechanical work and gap adjustment. Avoid if you want OEM reliability or need a clutch for heavy commercial use.