Cat Backhoe Thumb Cylinders

Cat Backhoe Thumb Cylinders parts list
Image	Fits Model	Description	Details	Part #	Price	Product Details
	See Details	416D/E/F, 420D/E/F, 430D/E/F, 450E/F, 307D, 308D, 308E, 308E2 CR	Thumb Cylinder Seal Kit		2764172	$54.00	View Info

Thumb cylinders and thumb cylinder seal kits for Caterpillar backhoe loaders, covering hydraulic components that power the mechanical thumb attachment across D, E, and F series machines.

Fits Models At A Glance

416 Series: 416D, 416E, 416F
420 Series: 420D, 420E, 420F
430 Series: 430D, 430E, 430F
450 Series: 450E, 450F

Key Notes

Application: Actuates the backhoe thumb for gripping and handling material
Components: Complete thumb cylinders and matching seal kits available
Part Reference: Seal kit 2764172 covers common thumb cylinder rebuilds
Condition: New and used cylinder assemblies to match your budget

Why Choose Broken Tractor

✅ Verified fitment across multiple Cat backhoe series
✅ Fast shipping from two US locations
✅ Knowledgeable staff to confirm your part

Frequently Asked Questions

What does the thumb cylinder do on a Cat backhoe?

The thumb cylinder is the hydraulic cylinder that powers the mechanical thumb attachment on a Caterpillar backhoe loader. It opens and closes the thumb against the bucket so the operator can grip and handle material like logs, rock and debris. Broken Tractor carries complete thumb cylinders and matching seal kits for Cat D, E and F series backhoes.

Which Cat backhoe models does thumb cylinder seal kit 2764172 fit?

Seal kit 2764172 fits the Cat 416D, 416E, 416F, 420D, 420E, 420F, 430D, 430E, 430F, 450E and 450F backhoe loaders. It covers common thumb cylinder rebuilds on these machines. Match the part number to your existing cylinder before ordering.

Should I rebuild or replace a Cat backhoe thumb cylinder?

If the cylinder body and rod are in good shape, a rebuild with seal kit 2764172 is usually the lower cost option for 416D through 450F machines. If you would rather replace the whole unit, Broken Tractor offers new and used thumb cylinder assemblies to fit different budgets. Our staff can help you decide which option makes sense for your machine.

How do I find the right thumb cylinder for my Cat 420E backhoe?

Start with your backhoe model and serial number, since fitment can vary by machine. Matching the part number on your current cylinder or seal kit is the most reliable way to get the correct part. For help confirming fitment on a 420E or any other Cat backhoe, call the Broken Tractor parts team at (800) 909-7060.