GX20072 Deck Belt 42 inch Fits John Deere D110 D100 D105 D120 D125 D130 L100 L110 E110 E120 E130 E100 LA105 LA110 LA115 S120 S100 GY20570 Lawn Mower

What It Is

This is a 42-inch deck drive belt for John Deere lawn tractors, transferring power from the engine pulley to the mower blades. It’s designed for 100 and LA Series tractors with a 42-inch cutting deck.

Fitment & Compatibility

Always verify your deck size – this belt only fits 42-inch decks, not 48 or 54. Compatible models include D100, D105, D110, D120, D125, D130, L100, L110, E100, E110, E120, E130, LA105, LA110, LA115, S100, S120. It replaces OEM part GY20570 and aftermarket GX20072. Measure your old belt – it should be 1/2 inch wide and approximately 92.5 inches long. Check your deck’s belt routing diagram (on deck or owner’s manual) to confirm routing matches this belt’s length.

Key Things to Know

• Installation difficulty: Moderate – requires removing the deck or using a belt tool to route around pulleys. No special tools needed but be patient.
• Quality: Aftermarket belt, good value for the price. Some users report slightly shorter lifespan than OEM (1-2 seasons vs 2-3), but fine for residential use.
• Common gotcha: The belt may be tight on first install. Ensure it’s fully seated in all pulley grooves before engaging the blades. Loose routing causes slipping or premature wear.
• Check deck spindles: Worn or seized spindles will kill any belt quickly – spin blades by hand to ensure smooth rotation before installing.

Should You Buy It

Yes, if you need a reliable, budget-friendly replacement for a residential John Deere 42-inch deck. It’s a solid aftermarket option that fits correctly and works well for typical weekly mowing. Skip it if you mow commercially or want maximum longevity – spring for the OEM GY20570 instead.