GY20852 48 inch 7-Star Mulching Toothed Blades for John Deere GX21784 D140 E140 D160 E150 E160 E170 LA145 LA140 LA155 155C 48" Decks 100 Series Tractor Zero Turn Mower GX21785 AM137757 2-Pack, Black

What It Is

This is a 2-pack of 48-inch mulching blades designed for a range of John Deere tractors and zero-turn mowers equipped with a 48-inch deck. The seven-star toothed design lifts and recuts grass clippings into fine particles for natural lawn feeding.

Fitment & Compatibility

Before buying, verify these three things:

1. Deck size: Your mower must have a factory 48-inch deck. Measure deck width if unsure—these blades will not fit 42-inch or 54-inch decks.
2. Model fit: Confirmed for John Deere D140, D160, E140, E150, E160, E170, LA145, LA140, LA155, 155C, and 100 Series tractors. Also fits zero-turn models using GX21784 or GX21785 OEM blades. This is an aftermarket replacement for OEM parts AM137757 and GX21785.
3. Blade measurements: Each blade is 19-3/4 inches long, 2-1/4 inches wide, with a 7-point star center hole and a 0.25-inch thickness. Measure your current blade length and center hole shape—if you have a round or oval hole, these won’t mount.

Key Things to Know

• Quality vs. OEM: These are budget-friendly aftermarket blades. They cut well but may dull faster than genuine John Deere blades, especially in sandy or tough grass.
• Installation difficulty: Moderate. Use a torque wrench to tighten to 70-90 ft-lbs. The star center hole aligns easily, but ensure the blade orientation matches the cutting direction (sharp edge forward).
• Common gotcha: These are mulching blades, not lift or bagging blades. They leave clippings on the lawn—do not expect clean side discharge or full bagging performance.
• Balance check: Out of the box, some users report slight imbalance. Test spin the blade on a balancer before installing to avoid vibration.

Should You Buy It

Buy these if you have a confirmed 48-inch John Deere deck, prioritize mulching over bagging, and want a low-cost replacement for routine blade swaps. Skip them if you need bagging blades or prefer OEM durability for heavy commercial use.