John Deere Original Equipment Mower Blades (GX22151) - UC21583

What It Is

This is a set of John Deere Original Equipment (OEM) mower blades (part #GX22151, also cross-referenced as UC21583) designed for use on select John Deere zero-turn and lawn tractors. They are high-lift blades intended for mulching or bagging grass in residential and light commercial mowing.

Fitment & Compatibility

• Deck size and model: Fits 48-inch and 54-inch mower decks on models including Z425, Z445, Z465, Z525E, Z535M, Z545R, X304, X320, X324, X340, X360, and X380. Always verify your specific model and deck size before buying.
• OEM vs aftermarket: These are genuine John Deere parts, not aftermarket. OEM ensures exact fit, balance, and material specs—aftermarket blades may vary in thickness, hole alignment, or lift profile.
• Measurements: Each blade is 18.5 inches long, 2.5 inches wide, with a 1-inch center hole and a 0.625-inch offset hole. Measure your old blade to confirm.
• Set content: Sold as a set of three blades (one per spindle). Check if your deck uses two or three blades; this set covers three-spindle decks only.

Key Things to Know

• Installation difficulty: Moderate. Requires lifting the mower, removing the deck, and using a socket wrench (usually 15/16” or 5/8” bolt). Torque blade bolts to 70-85 ft-lbs. No special tools beyond a blade removal tool or block of wood to hold the blade.
• Quality: OEM blades are made from heat-treated boron steel, which holds an edge longer than budget steel. Expect 20-30 hours of mowing before noticeable dulling, depending on grass type and debris.
• Common gotcha: The high-lift design creates strong airflow for bagging but can cause clumping in wet grass. Not ideal for dry, sandy soil (accelerates wear). Also, these blades are not for side-discharge only—they work best with bagger or mulching kits.
• Balance: Pre-balanced from the factory, but always check balance after sharpening. An unbalanced blade vibrates, damages spindles, and cuts unevenly.

Should You Buy It

Buy these if you own a compatible John Deere model (48” or 54” deck) and want reliable OEM quality for bagging or mulching. They’re a solid choice for residential mowing with occasional light commercial use. Skip them if you only side-discharge or need a cheaper aftermarket alternative—generic blades cost less but may lack the precise fit and durability.