GX21380 Medium Lift Blades for John Deere D170 54 inch Deck Lawn Mower Blades for GY20679 GY20684 GY20686 G110 190C LA150 S180 3 Pack

What It Is

The GX21380 3-pack of medium lift blades is an aftermarket replacement set for 54-inch John Deere mower decks. Designed for medium-duty cutting in grass and light debris, these blades deliver a clean cut without the aggressive suction of high-lift blades, making them ideal for standard residential lawns.

Fitment & Compatibility

Before buying, confirm your mower has a 54-inch deck—these blades will not fit smaller decks. Compatible with John Deere models including D170, G110, 190C, LA150, S180, and others using OEM part numbers GY20679, GY20684, or GY20686. Measure your existing blade: these are 21 inches long, 2.5 inches wide, with a 1-inch center hole and 0.5-inch oval pin hole. Verify the blade alignment matches your spindle—oval pin hole orientation varies by model. Aftermarket; not OEM, but direct replacement for listed models.

Key Things to Know

• Installation difficulty: Easy—requires a socket wrench and blade removal tool. Torque bolts to 50-70 ft-lbs (check your manual).
• Balance: Aftermarket blades may need balancing before install to prevent vibration and spindle wear. Use a blade balancer.
• Lift style: Medium lift is a compromise—good for grass, less effective for wet or thick mulch. Not for bagging or heavy leaf mulching.
• Durability: Heat-treated steel holds up well for typical residential use, but not as thick as OEM heavy-duty options. Expect 1-2 seasons with regular sharpening.

Should You Buy It

This is a solid budget-friendly choice for D170, LA150, or similar John Deere owners with a 54-inch deck who want a reliable replacement without paying OEM prices. Ideal for flat lawns and moderate cutting conditions—skip if you need high-lift for wet grass or heavy bagging.