GX20072 GY20570 Mower Deck Belt for John Deere 42 Inch Deck D105 D110 D130 E100 S100 L100 LA105 LA115, Kevlar Cord, 1/2" x 103-7/8"

What It Is

This is an aftermarket replacement deck belt for 42-inch cutting decks on select John Deere lawn tractors. It uses Kevlar cord reinforcement for durability, sized at 1/2-inch width by 103-7/8 inches length.

Fitment & Compatibility

Before buying: Confirm your mower has a 42-inch deck (measure deck shell if unsure). Compatible with John Deere models D105, D110, D130, E100, S100, L100, LA105, LA115, and similar L/LA series tractors using OEM belt #GX20072 or GY20570. This is an aftermarket belt, not genuine John Deere. Measure your old belt end-to-end (flat, not twisted) to verify 103-7/8 inches. Belt width must be 1/2 inch—wider or narrower will slip or not track properly.

Key Things to Know

• Quality: Kevlar cord is stronger than standard rubber belts, but aftermarket belts may wear faster than OEM in heavy use (e.g., thick grass, debris).
• Installation: Moderate difficulty—requires removing the deck, routing around tensioner and pulleys, and re-tensioning. Refer to your deck diagram.
• Common gotcha: The 103-7/8 inch length is critical; a belt that’s even 1/2 inch off can cause poor engagement or premature wear.
• Check pulleys: Worn or misaligned pulleys will destroy any belt quickly—inspect and replace if needed.

Should You Buy It

Buy this if you need a budget-friendly replacement for a 42-inch John Deere deck belt and you’re comfortable with a DIY install. It’s a solid value for light-to-moderate use. Skip it if you mow commercially or want OEM durability—stick with a genuine John Deere belt instead.