5/8" X 143.5" Deck Replacement Belt for Cub Cadet MTD Troy-Bilt 754-05078 954-05078 CMXGZAM501083 490-501-M070 490-501-C070, 50 Inch Deck Ultima Series ZT1-50, ZT1-50 KW, ZT2-50 KW and ZT1-50 KH

What It Is

This is a 5/8" wide, 143.5" long deck drive belt designed for 50-inch cutting decks on Cub Cadet Ultima Series ZT1-50, ZT1-50 KW, ZT2-50 KW, and ZT1-50 KH zero-turn mowers. It replaces OEM part numbers 754-05078, 954-05078, CMXGZAM501083, 490-501-M070, and 490-501-C070, and also fits select MTD and Troy-Bilt models with the same deck size.

Fitment & Compatibility

Before buying, verify these three things:

• Deck size: Must be exactly 50 inches (not 46" or 54"). Measure your deck or check the model number.
• Belt dimensions: Confirm your old belt is 5/8" wide and 143.5" long. If your belt is 1/2" or 3/8" wide, this won’t fit the pulleys.
• OEM cross-reference: Look for 754-05078, 954-05078, or CMXGZAM501083 on your old belt or mower manual. This is an aftermarket replacement, not genuine Cub Cadet, so it may differ slightly in material or stiffness.

Key Things to Know

• Quality vs. OEM: Aftermarket belts like this often cost less than half of genuine Cub Cadet belts, but some users report shorter lifespan (1-2 seasons vs 3-4 seasons for OEM) under heavy use.
• Installation difficulty: Moderate. You’ll need to remove the deck, release belt tension (spring-loaded idler pulley), and route the belt per the deck diagram. No special tools required, but a second person helps with tension.
• Common gotcha: The belt may feel slightly stiffer than OEM, requiring extra force to seat onto pulleys. If it squeaks after installation, re-check belt routing and pulley alignment.
• Storage note: Store the mower indoors to prevent belt cracking from UV and moisture, which affects aftermarket belts more than OEM.

Should You Buy It

Buy this if you need a budget-friendly replacement for a Cub Cadet Ultima ZT1 or ZT2 with a 50-inch deck and are comfortable with moderate DIY installation. It’s a solid value for light-to-medium use, but if you mow commercially or want maximum durability, spring for the genuine Cub Cadet belt.