3 Pack 918-06978 Spindle Assembly with 756-05034A Idler Pulley 954-05025A Belt Replace 618-06978 for Cub Cadet XT1-ST54, XT1-GT54, XT2-GX54, XT2-ST54, XT1 ST54, XT1 GT54, XT2 GX54 Tractors

What It Is

This is a 3-pack of spindle assemblies plus a replacement idler pulley and drive belt for 54-inch deck Cub Cadet XT1 and XT2 lawn tractors. It replaces the OEM 618-06978 spindle assembly and includes the 756-05034A idler pulley and 954-05025A belt, giving you everything needed to refresh the deck’s blade drive system.

Fitment & Compatibility

Before buying, confirm your mower has a 54-inch stamped steel deck—this kit is specifically for XT1-ST54, XT1-GT54, XT2-GX54, and XT2-ST54 models. Measure your deck width and check the model number on the frame tag near the battery or under the seat. This is an aftermarket replacement for OEM part 618-06978; the included idler pulley (756-05034A) and belt (954-05025A) are direct-fit for these decks. Verify your current spindle bolt pattern and pulley diameter (typically 4.5-inch pulley) match the new units—most 54" Cub decks from 2015 onward use the same geometry, but older or non-Cub decks will not work.

Key Things to Know

• Quality vs OEM: Aftermarket spindles in this kit are generally comparable to OEM, but check the bearing quality—some users report slightly shorter lifespan than genuine Cub Cadet parts. If you mow thick grass or rough terrain, consider OEM for the spindles.
• Installation difficulty: Moderate. You’ll need a socket set, jack or blocks to lift the deck, and a puller if the old spindles are seized. Expect 1–2 hours for all three.
• Common gotchas: The belt may be slightly tight on first install—use a tensioner tool or pry bar to fit it. Also, the idler pulley mounting bolt often seizes; soak it with penetrating oil before removal.
• What’s not included: Blade bolts, lock washers, or grease fittings. Reuse your old hardware if it’s in good shape, or buy new grade 8 bolts separately.

Should You Buy It

This is a solid value for DIYers who want a complete deck refresh in one order—especially if your spindles are noisy or wobbling and the belt is glazed or cracked. It’s not for you if you need OEM-only parts for warranty reasons or if you’re working on a different mower brand or deck size. For the price, it saves you from sourcing three separate items.