GX20072 John Deere 42 Inch Deck Belt, D105 D110 D130 S100 L110 L100 L111 LA105 LA115 LA125 S110 S130 E100 E110 L108 Lawn Mower, GY20570 V-Belt, Zero-Stretch, Extra Long Life /104 Inch

What It Is

This is a 104-inch zero-stretch V-belt designed to drive the mower blades on John Deere 42-inch cutting decks. It replaces OEM part numbers GX20072 and GY20570, and fits a wide range of Deere lawn tractors including D105, D110, D130, S100, L100, L110, L111, LA105, LA115, LA125, S110, S130, E100, E110, and L108 models.

Fitment & Compatibility

Before buying, confirm your mower has a 42-inch stamped steel deck (not a 42-inch fabricated or 48-inch deck). Measure your existing belt length—it should be exactly 104 inches. Check your owner’s manual or the belt part number printed on the old belt; it must match GX20072 or GY20570. This is an aftermarket replacement, not OEM John Deere, but it’s designed to identical dimensions. Verify your deck spindle and pulley configuration is standard (three-spindle, two-idler) for a 42-inch Edge or Accel Deep deck.

Key Things to Buy

• Zero-stretch construction means it won’t lengthen over time, keeping blade engagement consistent and reducing the need for retensioning.
• Installation is moderate difficulty—you’ll need to remove the deck or access it from under the mower. Route the belt exactly as shown in your deck diagram (typically around the two outer spindles, under the idler pulleys, and around the center spindle).
• Common gotcha: If your deck has a spring-loaded tensioner, ensure it’s fully released before installing the belt. Forcing it on can damage the belt or pulleys.
• 5.0 rating is based on only one review, so treat that as preliminary. The price is significantly lower than OEM ($15.99 vs. $30–$40 for John Deere brand).

Should You Buy It

If you own one of the listed John Deere models with a 42-inch deck and need a reliable, long-lasting belt without paying OEM markup, this is a solid choice. The zero-stretch design adds durability, and the price is hard to beat. However, if you prefer the peace of mind of an OEM part or your mower is under warranty, stick with the genuine John Deere belt.