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Cat 303.5 303CR Rear Idler

Cat 303.5 303CR Front Idler 172-2100
Cat 303.5 303CR Rear Idler
Buy aftermarket Cat mini excavator parts for your 303.5 and 303CR online at Rubbertrax and save versus going to your local dealer. Our parts are guaranteed to fit. The front idler wheel is designed for the Cat 303.5 and 303CR models. Parts may vary for sub-models. Get free shipping when you order online and ship to a commercial address.
SKU: 172-2100
Weight: 52 lbs
Make: Cat
Price: $380.00

Rubber tracks and wear parts are sold individually unless specified in the details. We offer free shipping across the USA when you order online and ship to a commercial address. *Some restrictions apply.

172-2100 Tension Idler Assembly

This is the aftermarket replacement rear idler for the following Cat mini excavators:

  • Cat 303.5
  • Cat 303CR

The tension idler installs on the opposite end of the undercarriage from the sprocket and this is the part that expands out as you pump the grease in the tensioner to tighten the rubber track. Some people refer to this larger roller as the pulley.

Alternate Part Numbers

  • Cat® Dealer Part Number: 172-2100

Alternate Models

This idler (172-2100) is known to fit:

  • Cat® 303.5
  • Cat® 303CR

Cat 303.5 Undercarriage