Youxmoto Deck Spindle Assembly for 54in MTD/Cub Cadet/Troy-Bilt — 3-Pack, OEM Fit with 6-Point Pulley

Youxmoto 918-06978 deck spindle assembly (3-pack) is a direct-fit replacement spindle for 54-inch MTD, Cub Cadet and Troy-Bilt mower decks, delivering OEM-style dimensions and a durable 6-point star pulley for reliable cutting performance.

When a worn spindle causes vibration, uneven cuts, or noisy operation, swapping in a correct replacement spindle restores deck alignment and blade speed without expensive dealer visits. This Youxmoto spindle kit matches the common OEM reference numbers used across many models and years, and the pack of three gives you spares or a full-deck refresh for walk-behind and zero-turn machines with a 54" deck.

Which mower models and part numbers does this spindle replace?

This spindle assembly is engineered to replace several OEM numbers used by MTD, Cub Cadet and related brands. It fits a wide range of 54" decks across model years, so you can match based on the spindle reference or the mower model listed below.

• Replaces MTD part numbers 618-06978 and 918-06978.
• Direct-fit for Cub Cadet references: 1427A3ZW099, 14A7A3ZW299, 14ARCACA099, and listed OEM codes.
• Compatible with many Cub Cadet RZT and XT series (RZT-L54, RZT-S54, XT1-ST54, XT2-GX54, ZT1-54, ZT2-54 and select year ranges).
• Troy-Bilt models supported include multiple TB2454, Super Bronco and Mustang 54 variants across 2015–2018 models.

How do size and mechanical details affect fit and performance?

This spindle matches the key physical dimensions that determine fit and belt alignment, so swapping is straightforward when the specs align. The assembly measures approximately 174.2 mm tall and uses a 138 mm outer pulley diameter, plus a 6-point star pulley design that secures blade pulleys consistently.

• Overall height: 6 6/7 inches (174.2 mm) for correct deck clearance.
• Pulley outer diameter: 5 7/16 inches (138 mm) to match belt path and tension.
• 6-point star pulley pattern for secure blade engagement.
• Sold as a 3-pack for full-deck replacement or spare parts.

What should I check before ordering to ensure compatibility?

Measure your existing spindle and compare part numbers, pulley diameter, and overall height to avoid returns. Also confirm bolt pattern and shaft type on your deck; checking the OEM reference numbers on your machine makes cross-referencing the easiest route to a correct match.

• Compare OEM part numbers stamped or listed in your manual (618-06978 / 918-06978).
• Measure pulley OD and spindle height on the existing assembly.
• Verify the bolt-hole pattern and blade shaft interface for a direct swap.
• Consider the 3-pack if you plan to service the entire 54" deck.

How difficult is installation and what tools are typically required?

Installation is moderate DIY work for someone comfortable under the deck and with basic mechanical tools. You’ll need to safely support the mower, remove belts and blades, unbolt the old spindle, and torque the new assembly to factory specs.

• Common tools: socket set, torque wrench, screwdrivers, and safety gloves.
• Recommended: service manual for torque specs and belt routing diagrams.
• Allow time for blade balancing and belt reinstallation after fitment.
• Professional installation is optional if you prefer shop-level service.

Who is this for: Youxmoto’s 918-06978 3-pack spindle assembly is aimed at homeowners, landscapers, and repair shops that maintain 54" decks on MTD-derived, Cub Cadet, and Troy-Bilt machines. If you need an economical, OEM-dimension replacement to restore smooth cutting and correct belt alignment—especially when multiple spindles are worn—this pack gives you three ready-to-install assemblies to finish the job in one visit.