[Upgraded Grip120] M154960 Secondary Deck Belt for 54 Inch John Deere GX255 GX335 GX355 X540 X320 X530 X590 Lawn Mower - Replaces M143923 | 5/8" x 120.6"

[Upgraded Grip120] M154960 Secondary Deck Belt for 54 Inch John Deere GX255 GX335 GX355 X540 X320 X530 X590 Lawn Mower - Replaces M143923 | 5/8" x 120.6"

Key Features

• Part Number: M154960
• Type: Secondary Deck Belt
• Application: For 54-inch mower decks with a two-belt system
• Dimensions: 5/8 in. Width x 120.6 in. Outer Circumference
• Material: Reinforced synthetic rubber construction for durability and grip

Replaces / Cross-Reference Part Numbers

• John Deere: M154960, M143923

Compatibility & Fitment

• Brand: John Deere
• Deck Size: 54 inches
• Fits Models: GX255, GX335, GX355, X320, X530, X540, X590
• Note: This secondary belt is for mower decks that utilize a two-belt configuration. Verify your specific deck requirements.

When to Replace

• Visible damage such as cracking, fraying, glazing, or separation
• Audible squealing or slipping during blade engagement
• Reduced or inconsistent blade speed leading to an uneven cut
• Belt frequently dislodges from pulleys

Installation Tips

• Disconnect the spark plug wire before beginning work for safety.
• Refer to your mower's service manual for the correct belt routing diagram.
• Clean debris from all pulleys and inspect them for damage or wear.
• Ensure the belt is correctly seated in all pulley grooves before tensioning.
• Check and adjust belt tension as specified by the manufacturer after installation.