GICOOL GX20249 Mulching Mower Blades for John De ere 42 Inch L100, L110, L111, L118, LA100, LA105, Replaces OEM GX20249, GX20433, GY20567, M128485, 11/16" Round Center Hole

What It Is

A set of two mulching blades designed for John Deere 42-inch cutting decks on select L and LA series tractors. Their curved, wing-like shape chops clippings finer than standard blades, allowing grass to decompose faster and eliminating the need for bagging.

Fitment & Compatibility

• Deck size: Only compatible with 42-inch decks. Measure your deck if unsure.
• Mower models: Fits John Deere L100, L110, L111, L118, LA100, LA105. Also fits many other L/LA series with a 42-inch deck (e.g., L120, LA110, LA115, LA125, LA130, LA135, LA140, LA145, LA150, LA155, LA165, LA175). Check your model number on the deck or under the seat.
• OEM replacements: Replaces John Deere part numbers GX20249, GX20433, GY20567, and M128485.
• Center hole: 11/16-inch round – measure your blade’s center hole before buying. If yours is a different size (e.g., 7/8-inch star), these will not fit.
• Aftermarket vs OEM: These are aftermarket blades, not John Deere OEM. They are typically made of a similar hardened steel but may have a slightly different finish or balance. They are generally interchangeable if dimensions match.

Key Things to Know

• Installation: Straightforward – lift the deck, remove the old blade bolt (left-hand thread on many John Deere decks – turn clockwise to loosen), install new blade with the sharp edge facing the direction of rotation (usually upward toward the deck). Torque bolt to 40-50 ft-lbs.
• Mulching performance: Works best with a mulching plug installed in the deck discharge chute. Without it, blades will still cut but won’t recirculate clippings as effectively.
• Sharpness: Blades come unsharpened from the factory. You’ll need to sharpen them before first use (or use them as-is for a brief break-in cut). A file or bench grinder works.
• Balance: After sharpening, check blade balance. An unbalanced blade causes vibration, noise, and premature spindle wear. A simple blade balancer is cheap insurance.

Should You Buy It

If you own a John Deere L or LA series with a 42-inch deck and want to mulch grass instead of bagging, these are a solid, affordable choice. They directly replace OEM blades at a lower cost and are rated highly for fit and durability. Just confirm your center hole size and be ready to sharpen them before cutting.