GX20072 Deck Belt 1/2" x 104" Compatible with John Deere D100, D105, D120, D125, D130, E100, E130, L100, L110, L111, L118, LA115 GY20570 42'' Riding Mower/Tractors

What It Is

This is a replacement deck belt for 42-inch cutting decks on select John Deere lawn tractors. It drives the mower blades from the engine pulley, sized at 1/2 inch wide by 104 inches long.

Fitment & Compatibility

Before buying, confirm your mower has a 42-inch deck and that the original belt part number is GY20570 or GX20072. This belt fits models: D100, D105, D120, D125, D130, E100, E130, L100, L110, L111, L118, LA115. Measure your current belt’s length (end-to-end, flat) and width—if it’s not exactly 1/2" x 104", this won’t work. Check your deck’s spindle pulley diagram; some models use a different belt routing or length for 42" decks. OEM cross-reference includes John Deere part GY20570.

Key Things to Do

• Check belt routing: Look up your model’s deck diagram online—routing varies even within the same deck size. Wrong routing will cause slipping or blade damage.
• Installation difficulty: Moderate. You’ll need to remove the deck or at least the belt cover. A belt tensioner tool helps, but a socket wrench often works.
• Quality note: This is an aftermarket belt, not OEM John Deere. At $9.99, it’s a budget option. Expect shorter lifespan than a $20+ OEM belt, especially on heavy-use or rough terrain.
• Common gotcha: Old belts can stretch—if your mower vibrates or blades stop engaging after install, re-check routing and tensioner spring condition.

Should You Buy It

If you need a quick, low-cost fix for a 42-inch John Deere deck and don’t mind replacing it more often, this belt will get your mower cutting again. It’s right for light-duty residential use—skip it for commercial or heavy acreage mowing where a premium OEM belt is worth the extra money.