8TEN Spindle Mulching Blade Kit for John Deere 42 inch Deck 115 125 135 LA 100 105 110 120 125 135 X106 X110 X120 D110

What It Is

This is a set of three mulching blades designed to replace the stock blades on John Deere 42-inch Edge, Econ, and standard cutting decks. They chop clippings finer for better nutrient recycling, ideal for lawn owners who want to skip bagging.

Fitment & Compatibility

• Deck size: Only fits John Deere 42-inch decks (Edge, Econ, or standard). Measure your deck width or check the deck model number stamped on the deck housing.
• Compatible models: 115, 125, 135, LA100/105/110/120/125/135, X106, X110, X120, D110 (and similar LA/X series with 42-inch decks). Not for 38-inch or 48-inch decks.
• OEM vs aftermarket: Aftermarket replacement for OEM part numbers GY20786, GY20785, or GY21112. Check your current blade’s part number under the deck or in your manual.
• Measurements: Each blade is approximately 16.5 inches long, 2.5 inches wide, with a 0.25-inch center hole and a 1-inch diameter center hole (fits standard John Deere spindle). Verify your spindle bolt pattern—these use a 5-point star center hole, not a round hole.
• What to check before buying: Confirm your deck is 42 inches (not 38 or 48), verify your blade hole shape (star vs round), and ensure you have a mulching setup (no side discharge chute installed—these blades need a plug or cover).

Key Things to Know

• Quality: Made from heat-treated steel; reviews note they stay sharp longer than OEM blades for most users, but some report slight imbalance out of the box—balance check recommended before install.
• Installation difficulty: Moderate. You’ll need a socket wrench and possibly a blade removal tool. Torque bolts to 70-90 ft-lbs (check your manual). Lift the deck or remove blades safely—disconnect spark plug first.
• Common gotcha: These are mulching blades only—they won’t bag or side-discharge effectively. If you switch between modes, you’ll need to swap blades.
• Deck prep: Clean the deck underside before installing to avoid debris buildup that can reduce mulching performance.

Should You Buy It

Buy this kit if you own a compatible John Deere 42-inch deck and want a durable, budget-friendly mulching upgrade that reduces bagging frequency. Skip it if you need bagging or side-discharge performance, or if you have a 38-inch or 48-inch deck.