Spindle Assembly 618-06978 for Cub Cadet RZT-L54 54-Inch Deck

Overview

This aftermarket 618-06978 spindle assembly is a replacement-style mower deck spindle assembly for select Cub Cadet 54-inch RZT mower deck applications.

This listing is organized around the 618-06978 / 918-06978 spindle path. Some package options may include additional deck repair components such as spindle reinforcement rings, blades, and a deck belt, but the lead replacement path is the spindle assembly.

Key Features

• Aftermarket replacement-style mower deck spindle assembly with pulley
• Product Type: Spindle Assembly
• Lead Part Number: 618-06978
• Also Replaces: 918-06978
• Common Deck Reference: 54 inch
• Optional package variants may include spindle assemblies, reinforcement rings, blades, and deck belt components
• Organized by spindle or mandrel part number first to reduce fitment confusion

Compatible Brands & Model Series

This 618-06978 spindle assembly is associated with select Cub Cadet 54-inch RZT mower deck applications.

Cub Cadet model references include:

• RZT-L54
• L54KH
• L54KW
• RZT-S54 KW
• RZT-L54 KH

Verify your part numbers before ordering.

Replaces OEM Part Numbers

• Cub Cadet / MTD: 618-06978, 918-06978

Optional Package Part Number Breakdown

Part numbers below may apply to optional package variants. Not every package includes every component listed. Select the package option that matches the parts needed for your repair.

• Spindle / Mandrel Numbers: 618-06978, 918-06978
• Deck Repair Ring: Reinforcement ring included in select package options; no separate ring part number provided
• Blade Numbers: 742-0677, 742-0677A, 742-0677B, 942-0677, 942-0677A, 942-0677B, OCC-742-0677
• Deck Belt Numbers: 754-04329, 754-04329A, 954-04329, 954-04329A

Single Spindle Specifications

• Spindle Part Number: 618-06978
• Also Replaces: 918-06978
• Deck Size Reference: 54 inch
• Length: 175 mm / 6.88 inches
• Pulley Width: 19 mm / 0.74 inch
• Mounting Hole Distance: 125 mm / 4.92 inches

Optional Package Component Specifications

The following specifications apply to optional package variants that include reinforcement rings, blades, or deck belt components.

• Spindle Assembly Height: 174.2 mm
• Spindle Assembly Width: 147.7 mm
• Spindle Assembly Length: 147.7 mm
• Deck Repair Ring Length: 168 mm / 6.6 inches
• Deck Repair Ring Width: 168 mm / 6.6 inches
• Deck Repair Ring Height: 5 mm / 0.2 inch

Common Symptoms / When to Replace

• Mower deck spindle is noisy, loose, seized, or wobbling
• Blade has excessive play at the spindle shaft
• Deck vibration increases during blade engagement
• Pulley, blade, or belt system is worn, damaged, or no longer tracking correctly
• Original spindle number matches 618-06978 or 918-06978

Quick Ship Fulfillment

This item may ship directly from one of our trusted U.S. distribution partners to help reduce transit time. Packaging, labeling, or warehouse origin may vary, but the part will match the replacement numbers, fitment notes, and specifications shown in this listing.

Why Buy From PTO Direct USA

• Fitment-first product organization by replacement part-number path
• Clear spindle, reinforcement ring, blade, and belt references for package variants
• U.S.-focused fulfillment options for faster delivery when available

Need Help Confirming Fitment?

Send us your mower model number, deck size, and the part number stamped on your original spindle or mandrel assembly. We can help confirm whether this is the correct replacement path.

FAQ

Is this an OEM spindle assembly?

No. This is an aftermarket replacement-style spindle assembly intended to replace the listed part-number path when the physical fitment details match.

What is the lead part number for this listing?

The lead spindle part number is 618-06978. This listing also references 918-06978 in the same spindle path.

Do all package options include reinforcement rings, blades, and a belt?

No. Package contents vary by selected option. Use the variant title and product images to confirm whether you are ordering a single spindle assembly or a larger deck rebuild package.

Can I order by deck size only?

No. Deck size alone is not enough. Match the original spindle or mandrel number and confirm your mower model, deck setup, pulley layout, mounting pattern, blade path, and belt path before ordering.