GX20072 Deck Belt 1/2" x 104" for John Deere D100 D105 D110 D125 D130 L100 L110 E100 E110 E120 E130 LA105 LA110 LA115 S100 GY20570 42in Riding Mower/Tractors Replace GY20570

What It Is

This is a 1/2-inch wide by 104-inch long deck belt designed to drive the mower blades on 42-inch cutting decks. It replaces OEM part GY20570 and fits most John Deere 100 and 200 series lawn tractors, including D100, D105, D110, D125, D130, L100, L110, E100, E110, E120, E130, LA105, LA110, LA115, and S100 models. Primarily used for residential mowing, it’s a direct replacement for worn factory belts.

Fitment & Compatibility

Before buying, confirm three things: your deck size must be exactly 42 inches (models with 38-inch or 48-inch decks use different belts). Check that your mower is a John Deere 100/200 series listed above—this belt will not fit older or commercial models. Measure your old belt end-to-end (104 inches) and width (1/2 inch). This is an aftermarket belt, not OEM, but matches GY20570 precisely. Verify your belt routing diagram online for your specific model, as some require the belt to pass over or under specific pulleys.

Key Things to Know

• Quality: Users report this belt lasts one to two seasons with normal residential use. It’s a solid value at $13.99 but may wear faster than a premium OEM belt under heavy load or frequent mulching.
• Installation: Moderate difficulty. You’ll need to remove the deck or access pulleys from underneath. A belt routing diagram is essential—mistakes cause slipping or blade engagement failure. No special tools required, but a flathead screwdriver helps work the belt over pulleys.
• Common Gotcha: The 104-inch length is critical. A belt even 1/2 inch shorter or longer will not tension properly. Also, if your old belt snapped, check all pulleys and spindles for damage before replacing the belt.
• Lubrication: Not required for the belt itself, but ensure pulleys spin freely and are free of debris.

Should You Buy It

If you own a John Deere 100/200 series with a 42-inch deck and need an affordable, reliable replacement for light to medium-duty mowing, this belt is a smart buy. It’s not built for commercial use or heavy abuse, but for typical weekly lawn care, it offers solid performance at a fraction of OEM cost. Skip it if you need a longer-lasting belt for tough conditions or prefer genuine John Deere parts.