48" Deck Belt Idler Kit John Deere D140 D150 LA145 S170 X165 Z255 GX21833

Complete 48" deck belt and idler pulley kit for a wide range of John Deere 100, D, E, L, LA, S, X and Z Series riding mowers and zero-turn mowers.

This 4-piece maintenance kit replaces the major belt-routing wear components on compatible John Deere 48" decks: 1 deck drive belt, 2 small flat idler pulleys and 1 large idler pulley.

Designed around the popular GX21833 / GX20571 deck belt, GY20067 / GY22172 small idlers and GY20110 / GY20629 large idler configuration.

What's Included

OEM Part Number Cross-Reference

Deck Drive Belt:
GX20571, GX21833

Small Flat Idler Pulleys:
GY20067, GY22172

Large Idler Pulley:
GY20110, GY20629, GY22082, AUC17621

Component Specifications

Deck Drive Belt:
Approximately 1/2"–17/32" wide × 141"–141.7" nominal length depending on manufacturer measurement method • Replaces GX20571 / GX21833

Small Flat Idler Pulleys:
Approximately 3-5/8" OD × 11/16" ID × 1-3/16" high • 2 included

Large Idler Pulley:
Approximately 5-1/8" to 5-1/4" OD × 11/16" ID × 1-3/4" high • 1 included

Compatible John Deere 48" Models

100 Series

• 145
• 155C

D Series

• D140
• D150
• D155
• D160

E Series

• E140
• E150
• E160
• E170

L Series

• L120 — compatible later 48" deck configuration; verify serial number and OEM parts
• L130 — compatible later 48" deck configuration; verify serial number and OEM parts

For L120/L130 applications, the GX21833 belt and GY20067/GY20110 idler configuration is documented on later deck configurations. Because spindle and blade designs changed across production, always verify the original belt and pulley numbers before ordering.

LA Series

• LA130
• LA140
• LA145
• LA155
• LA165

S Series

• S140
• S150 — compatible 48" configuration; verify OEM numbers
• S160
• S170

X Series

• X140
• X165
• X166
• X167 — compatible 48" configuration using GX21833 belt and matching idlers

Z / EZtrak / ZTrak Series

• Z225 — compatible 48" configurations
• Z235 — compatible 48" configurations
• Z245 — compatible 48" configurations
• Z255
• Z355E — select earlier 48" configurations; verify serial number and OEM parts

Need Blades and Spindles Too?

Green Dade Outdoor also offers complete 48" deck rebuild kits that use this same GX21833 belt and GY20067 / GY20110 idler configuration and add the spindle assemblies and mower blades needed for a more complete deck overhaul.

Which Kit Do I Need?

Choose 80-DK-047 if your mower uses the GX21833 / GX20571 belt and matching GY20067 / GY20110 idlers and your existing blades and spindle assemblies are still in good condition.

Consider 80-DK-039 or 80-DK-018 when you also need to replace the spindle assemblies and mower blades. Compare the spindle and blade OEM numbers listed on each complete kit with the parts required by your specific mower.

This distinction is especially important on John Deere 48" decks because multiple generations may share the same deck belt and idler pulleys while using different spindle and blade designs.

If you are unsure which configuration your mower uses, compare the OEM numbers on your original parts or contact Green Dade Outdoor with your complete mower model and serial number before ordering.

Aftermarket replacement parts. John Deere and OEM part numbers are used for identification and compatibility reference purposes only.