756-04511B 756-05042 Flat Idler Pulley for MTD Craftsman Z6600 Cub Cadet RZT-L50 RZT-L54 RZT-S50 RZT-S54 Troy Bilt Mustang XP Fit 42" 46" 50" 54" Deck (3 Pack)

What It Is

This is a 3-pack of flat idler pulleys (models 756-04511B and 756-05042) for zero-turn mowers with 42", 46", 50", or 54" fabricated decks. They guide and tension the deck belt on MTD-built machines like Cub Cadet Z6600, RZT-L50/L54, RZT-S50/S54, and Troy-Bilt Mustang XP—replacing worn, noisy, or wobbling pulleys that cause belt slippage or poor cut quality.

Fitment & Compatibility

Before buying, check your mower’s model number (stamped under seat or on frame) against these confirmed fits:

• Decks: 42", 46", 50", 54" (fabricated, not stamped steel)
• Cub Cadet: Z6600, RZT-L50, RZT-L54, RZT-S50, RZT-S54
• Troy-Bilt: Mustang XP series (with 50" or 54" deck)
• MTD/Craftsman: Z4600, Z4800, Z5000 (verify deck type)

Critical checks:

• Measure your existing pulley: 3.5" diameter, 3/8" inner bore, flat face (no groove).
• These are aftermarket replacements for OEM part numbers 756-04511B and 756-05042. They may differ slightly in bearing quality or finish from OEM—inspect bearing spin and axial play before installing.
• Will not fit stamped steel decks or older MTD units with different bolt patterns. If your pulley has a grease fitting or a shoulder, these won’t match.

Key Things to Know

• Quality: Bearing quality varies. Some users report shorter lifespan than OEM—check for smooth spin and no wobble on install. If you mow heavy grass or rough terrain, consider OEM for durability.
• Installation: Moderate difficulty. Requires removing deck belt, cleaning debris, and torquing the center bolt to 25-30 ft-lbs. No special tools beyond a socket and ratchet. Replace all three at once to avoid uneven wear.
• Common gotcha: The included bolts may be slightly different length than OEM. Reuse your original hardware if the new bolts bottom out or don’t seat flush.
• Deck compatibility: Double-check your deck is fabricated (welded seams) not stamped (single sheet). These pulleys are designed for the heavier-duty fabricated decks on zero-turns.

Should You Buy It

Buy this 3-pack if you own a Cub Cadet RZT or Troy-Bilt Mustang XP with a fabricated deck and need an affordable, quick fix for worn idler pulleys—especially if you’re replacing all three at once. It’s a solid value for DIY maintenance, but if you want maximum longevity or are mowing commercially, stick with OEM pulleys.