Lawn Mower Spindle for MTD Troy-Bilt Craftsman Columbia Huskee Murray 42 inch Deck Lawn Tractors Mandrel Assembly Replacement Part Number 918-06991 618-06991 2-Pack

What It Is

This is a replacement mandrel assembly (spindle) for the cutting deck of select MTD-branded lawn tractors. It houses the bearings that spin the blade, and it’s designed for 42-inch side-discharge or mulching decks on Troy-Bilt, Craftsman, Columbia, Huskee, and Murray machines.

Fitment & Compatibility

Before buying, confirm your deck is exactly 42 inches (measured blade tip to blade tip). This spindle replaces OEM part numbers 918-06991 and 618-06991. It fits most MTD, Troy-Bilt, Craftsman, Columbia, Huskee, and Murray lawn tractors with a 42-inch deck made from the mid-1990s through the 2010s. Check your existing spindle for a stamped part number to verify. The assembly uses a 5/8-inch hex shaft and a 1-inch blade hole. Measure the bolt pattern (center-to-center distance between mounting holes) on your deck—this spindle uses a standard 3-inch pattern.

Key Things to Know

• Quality: This is an aftermarket replacement, not OEM. It’s generally reliable for residential use, but the bearings may not last as long as OEM in heavy commercial duty.
• Installation difficulty: Moderate. You’ll need a socket set, a torque wrench (tighten to 30-40 ft-lbs), and possibly a puller to remove the old spindle from the pulley.
• Common gotcha: The pulley is not included. Reuse your old pulley or buy one separately. Also, the mounting bolts often corrode—soak them with penetrating oil a day before removal.
• Two-pack value: You get two spindles for the price of one OEM. If your deck has two or three spindles, this is a cost-effective way to replace both at once.

Should You Buy It

Buy this if you have a 42-inch MTD-family tractor with a worn or noisy spindle and want a budget-friendly, two-pack option for DIY replacement. It’s a solid value for residential mowing, but skip it if you need OEM durability for heavy commercial use or if your deck uses a different bolt pattern or shaft size.