8TEN Mower Spindle for MTD Craftsman Troy Bilt 42 inch Deck T1200 Super Bronco Pony TB2246 618-06991 918-06991

What It Is

This is a replacement spindle assembly for the cutting deck on select MTD-built lawn tractors, including Craftsman, Troy-Bilt, and Yard Machines models with a 42-inch deck. It houses the bearings and pulley that spin the blade, and it’s commonly needed when your mower deck vibrates, makes grinding noises, or won’t cut evenly.

Fitment & Compatibility

• Deck size: Designed for 42-inch (107 cm) decks only. Measure your deck width before buying.
• Brands/models: Fits MTD, Craftsman (T1200, Super Bronco, Pony), Troy-Bilt (TB2246, Bronco), Yard Machines, and Cub Cadet with 42-inch decks.
• OEM cross-reference: Replaces MTD part numbers 618-06991, 918-06991, and 918-06991A.
• Physical check: Spindle has a 5/8-inch shaft diameter and uses a 1-inch hex nut on top. The housing bolt pattern is a 2.75-inch square (center-to-center). Measure your old spindle’s housing bolt spacing and shaft diameter to confirm.
• Watch for: Some 42-inch decks use a different spindle with a 3/4-inch shaft. If your blade hole is 5/8-inch, this fits. If it’s larger, you need a different spindle.

Key Things to Know

• Quality: Solid aftermarket part. Users report it’s comparable to OEM, with pre-installed bearings and a grease fitting. No need to press bearings in.
• Installation difficulty: Moderate. Requires removing the deck, belt, pulley, and blade. You’ll need a socket set, wrench, and possibly a puller for the pulley if it’s seized.
• Common gotcha: The pulley is not included. You must reuse your old pulley or buy a separate replacement. Also, the spindle housing may be slightly taller than OEM; check blade-to-deck clearance after install.
• Durability: Bearings are sealed and greased. With proper maintenance (occasional greasing), expect 2-3 seasons of regular use.

Should You Buy It

If you have a 42-inch MTD-based lawn tractor (Craftsman, Troy-Bilt, etc.) with a failing spindle and want a reliable, budget-friendly replacement that doesn’t require bearing pressing, this is a solid choice. It’s not for decks with 3/4-inch shafts or mowers from other brands like John Deere or Husqvarna.