GY20852 48" Lawn Mower Blades with 7 Point Star Shape, Mulching Blade Compatible with John Deere D140, E140, E170, S140 48" Deck Zero Turn Lawn Tractor, Replaces Number GX21784, AM137757, 3 Pcs

What It Is

This is a set of three 48-inch mulching blades designed for select John Deere zero-turn lawn tractors with a 48-inch deck. They feature a 7-point star center hole and are intended to chop grass clippings finer for better nutrient recycling.

Fitment & Compatibility

Before buying, confirm your mower deck is exactly 48 inches and uses a 7-point star spindle. Compatible models include John Deere D140, E140, E170, and S140—but only those with the 48-inch deck option. These blades replace OEM numbers GX21784 and AM137757. Measure your existing blade length (48-inch deck blades are typically 18.5–19 inches long) and check the center hole shape—a 7-point star, not a round or oval hole. Also verify your spindle bolt size (usually 5/8-inch).

Key Things to Know

• Quality: Budget aftermarket blades. Users report decent durability for residential use but note they may dull faster than OEM John Deere blades.
• Installation: Simple bolt-on job. Use a torque wrench—spec is typically 70–80 ft-lbs. Mark blade orientation before removal.
• Gotcha: The 7-point star must align perfectly with your spindle; some users report a tight fit requiring gentle tapping.
• Mulching performance: Works well for regular mowing but may struggle with wet or tall grass—consider bagging in those conditions.

Should You Buy It

Good value for homeowners with a compatible 48-inch John Deere zero-turn who want an affordable three-pack of mulching blades. Not ideal for commercial use or if you need OEM-grade longevity. Check your deck size and star pattern before ordering.