Deck Rebuild kit for John Deere L100 L105 L107 L108 L110 L111 L118 Riding Lawn Mowers Replace Part Number Spindle GY20785 GY20479 Blade GX20433 Belt GY20570 Idler Pulley GY20067 GY20629

What It Is

This deck rebuild kit replaces the entire cutting system for select John Deere L-Series lawn tractors (L100, L105, L107, L108, L110, L111, L118). It includes two spindles, two blades, a drive belt, and two idler pulleys—everything needed to restore a worn-out 42-inch or 48-inch stamped steel deck to like-new operation.

Fitment & Compatibility

• Deck sizes: Fits 42-inch (GY20433 blades) and 48-inch decks used on the listed L-Series tractors.
• OEM cross-references: Spindle GY20785/GY20479, Blade GX20433, Belt GY20570, Idler Pulley GY20067/GY20629.
• Check before buying: Measure your deck width (42" vs 48") and confirm your tractor model. Verify your belt length is 105.5" (GY20570) and pulley diameters match (4" idler, 4.5" tensioner). Also ensure your deck uses the older square-spindle design (pre-2010) rather than the newer round-spindle version.
• Not compatible with Z-Series zero-turn mowers or 54-inch decks.

Key Things to Know

• Quality: Kit uses aftermarket components—spindles are steel but may lack OEM bearing seals. Inspect for smooth rotation before install.
• Installation difficulty: Moderate. Requires removing the deck, swapping spindles (need a puller or hammer if rusted), and routing the belt correctly. Allow 2–3 hours.
• Common gotcha: The belt can be tricky to tension—use the idler pulley bracket to relieve tension, not brute force. Also, torque spindle nuts to 30–35 ft-lbs; overtightening can crack the housing.
• Blade alignment: After install, check blade tip height—uneven spindles can cause scalping. Shim if needed.

Should You Buy It

This kit is a solid value if your L-Series deck has worn spindles (wobble/noise), a frayed belt, or dull blades. It’s cheaper than buying each part separately and includes everything for a full refresh. Skip it if you only need one spindle or blade—buy individual parts instead. Good for DIYers comfortable with basic wrenching.