50 Inch Mower Deck Rebuild Kit for Cub Cadet MTD RZT 50 RZT 50VT RZT50 ZT50 ZT 50 Troy Bilt Mustang XP 50 Lawn Mower Spindle 618-04126 Blade 942-04053 Belt 754-04044 Idler 956-04129 Wheel 734-04155

What It Is

This is a comprehensive rebuild kit for 50-inch mower decks on Cub Cadet RZT and Troy Bilt Mustang XP 50 zero-turn mowers. It includes the spindle assembly, blade, belt, idler pulley, and gauge wheel needed to restore cutting performance on decks that are worn or damaged.

Fitment & Compatibility

• Deck size: 50 inches only. Measure your deck width to confirm.
• Models: Cub Cadet RZT 50, RZT 50VT, RZT50, ZT50, ZT 50, and Troy Bilt Mustang XP 50. Check your model number tag under the seat or on the frame.
• OEM vs aftermarket: This is an aftermarket kit using OEM-equivalent part numbers (618-04126, 942-04053, 754-04044, 956-04129, 734-04155). It should fit most 2005–2015 Cub Cadet and MTD 50-inch decks, but verify your existing part numbers match.
• Measurements: The spindle has a 1-inch shaft and uses a 3/8-inch bolt. Belt is 94.5 inches long (5/8-inch wide). Idler pulley is 4 inches OD. Gauge wheel uses a 5/8-inch bolt. Compare against your old parts.

Key Things to Know

• Quality concerns: Some users report the spindle bearings wear faster than OEM. Inspect the kit upon arrival for casting flaws or rough pulley edges.
• Installation difficulty: Moderate. You’ll need a socket set, torque wrench, and a spring puller for the belt tensioner. Allow 2–3 hours.
• Common gotcha: The belt may be slightly shorter than OEM (94.5 vs 95 inches). If your deck has an adjustable tensioner, it’s fine; if not, expect a tight fit.
• What’s not included: Blade bolts, spindle nuts, or deck hardware. Reuse yours or buy new.

Should You Buy It

This kit is a good value if you’re rebuilding a worn 50-inch Cub Cadet or Troy Bilt deck on a budget and don’t mind aftermarket parts. It’s not for you if you need OEM longevity or have a different deck size. Check all part numbers against your machine before buying.