MaxPower 561812XB Set of 3, 3-N-1 Commercial Mulching Blades for 48 in. Cut John Deere Mowers Replaces OEM no. GX21784, GX21786, GY20852

What It Is

This is a set of three aftermarket mulching blades for 48-inch cut John Deere commercial mowers. They’re designed for 3-in-1 operation (mulch, bag, side-discharge) and replace OEM part numbers GX21784, GX21786, and GY20852.

Fitment & Compatibility

Before buying, confirm your mower deck is exactly 48 inches (not 42, 54, or 60). These blades fit many John Deere models, including the 7000, 7500, 8500, and 9000 series, plus some X700 series. Check your owner’s manual or measure your current blades—these are 18.75 inches long, 2.5 inches wide, with a 0.25-inch thick center hole and a 7-point star drive. They will not fit standard spindle mounts (round or 5-point star). Verify your OEM part number matches one of the three listed.

Key Things to Know

• Commercial-grade steel – Thicker and harder than standard residential blades, but may require a sharpening before first use if you want a perfect cut.
• Installation is straightforward – Use a torque wrench to tighten to 70-90 ft-lbs. No special tools beyond a socket and breaker bar.
• Common gotcha – The set includes three blades, but some John Deere 48-inch decks only use two blades (check your deck’s spindle count). If you have a two-blade deck, you’ll have a spare.
• Balance check – After installation, spin the blades by hand. Any wobble means an unbalanced blade—return or re-balance.

Should You Buy It

If you own a 48-inch John Deere commercial mower and want a durable, cost-effective alternative to OEM blades, this set is a solid choice. It’s ideal for heavy mulching on large lawns or commercial properties, but skip it if you need a dedicated bagging or high-lift blade—these are best for mulching performance.