172-5636 CAT D11T D11R 22cc Piston Pump

Product Overview

The 172-5636 is a Caterpillar 22Cc Basic Slipper Piston Pump listed in the official Cat Parts Store. Caterpillar identifies it as a carbon-steel, counter-clockwise rotation piston pump for Track-Type Tractor pump drives and lists D11R and D11T as compatible models.

The official Cat listing also shows 10R-8686 as the corresponding Cat Reman alternative. The dedicated 10R-8686 page identifies it as a Cat Reman Hydraulic Pump and currently lists D11R as its compatible Track-Type Tractor application. Therefore, D11T users should verify the machine serial number and original configuration before treating 10R-8686 as a direct replacement.

From an aftermarket engineering perspective, 172-5636 / 10R-8686 should be treated as a complete replacement reference rather than a generic piston-pump description. Our replacement program focuses on interchangeability, dimensional matching, rotation verification, and 100% simulated operating-condition testing.

Part Number Identification

• CAT OEM Part Number: 172-5636
• Part Number without separator: 1725636
• Cat Reman Reference: 10R-8686
• OEM Product Description: 22Cc Basic Slipper Piston Pump
• Pump Type: Slipper Piston Pump
• Displacement: 22 cm³/rev
• Rotation: Counter-Clockwise
• Material: Carbon Steel
• OEM Compatible Models: D11R, D11T
• Current official 10R-8686 compatible model listing: D11R

Technical Specifications

• Brand: Caterpillar / CAT
• OEM Part Number: 172-5636
• Part Number without hyphens: 1725636
• Cat Reman Part Number: 10R-8686
• Product Description: 22Cc Basic Slipper Piston Pump
• Pump Type: Slipper Piston Pump
• Displacement: 22 cm³/rev
• Rotation Direction: Counter-Clockwise
• Material: Carbon Steel
• Official Published Length: 10.8 in
• Official Published Height: 10.0 in
• Official Published Width: Not published on the current Cat Parts Store page
• Compatible Models: D11R, D11T
• Rated Pressure: Not published on the current official public page
• Peak Pressure: Not published on the current official public page
• Maximum Speed: Not published on the current official public page
• Detailed Control Configuration: Not published for this specific part number
• Weight: Not published on the current official public page

Caterpillar’s official listing confirms the 22 cm³/rev displacement, carbon-steel construction, counter-clockwise rotation and published dimensions. (parts.cat.com)

No unverified third-party pressure, speed or control values have been substituted for missing OEM data.

Key Technical Advantages

1. 22 cm³/rev Slipper Piston Architecture

Caterpillar identifies 172-5636 specifically as a 22Cc Basic Slipper Piston Pump.

The slipper-piston architecture uses the piston, slipper and swashplate assembly to convert mechanical rotation into hydraulic flow. This design is well suited to heavy mobile equipment requiring a compact hydraulic pump for a defined machine function.

2. Confirmed Counter-Clockwise Rotation

The official Cat specification identifies counter-clockwise rotation for 172-5636.

Rotation direction must be checked before installation because a mechanically compatible pump can still fail to operate correctly if its drive direction is incorrect.

3. Carbon Steel Construction

Caterpillar specifies Carbon Steel for 172-5636.

For replacement manufacturing, material specification should be combined with accurate machining of the housing, shaft interfaces and critical rotating-group surfaces.

4. Clear OEM Part-Number Traceability

Caterpillar’s official catalog connects 172-5636 with 10R-8686 Cat Reman Hydraulic Pump.

This traceability provides a reliable reference for procurement and maintenance and reduces the possibility of selecting a visually similar but functionally different pump.

5. Compact Published Envelope

The official Cat dimensions for 172-5636 are:

• Length: 10.8 in
• Height: 10.0 in

These dimensions provide useful baseline data for checking installation clearance during replacement.

6. Replacement-Oriented Precision Control

A properly engineered aftermarket replacement should control:

• Rotating-group geometry
• Piston and slipper condition
• Swashplate contact
• Shaft and coupling fit
• Sealing surfaces
• Internal leakage
• Rotation direction
• Flow response

These engineering controls are more important than visual similarity alone when evaluating a hydraulic piston-pump replacement.

Application Areas

Caterpillar officially lists D11R and D11T Track-Type Tractors as compatible models for 172-5636. (parts.cat.com)

Typical applications include:

• Caterpillar D11R Track-Type Tractor
• Caterpillar D11T Track-Type Tractor
• Track-Type Tractor Pump Drive Systems
• Heavy-Duty Bulldozer Hydraulic Systems
• Mining and Earthmoving Equipment
• Large-Scale Earthmoving Operations

For D11T applications using 10R-8686, additional compatibility verification is recommended because the current official 10R-8686 listing identifies D11R rather than D11T.

Expert Maintenance Tips

1. Confirm Rotation Direction

The official specification for 172-5636 is counter-clockwise rotation. Confirm the actual pump-drive rotation before installation.

2. Verify the 172-5636 / 10R-8686 Relationship

Caterpillar lists 10R-8686 as the Cat Reman alternative for 172-5636.

However, because the current 10R-8686 page lists D11R as its compatible model, D11T installations should be verified against the actual machine serial number and original part configuration.

3. Inspect the Pump Drive Coupling

The Cat Parts Store parts diagram for 172-5636 includes a 138-4351 15-Tooth Internal Spline Shaft Coupling.

Before installing the replacement pump, inspect:

• Drive coupling
• Internal splines
• Shaft wear
• Coupling alignment
• Torsional wear

4. Control Hydraulic Contamination

Before commissioning:

• Inspect the reservoir
• Check the suction circuit
• Inspect or replace filtration
• Remove metallic contamination
• Use clean hydraulic oil
• Prevent air ingress

Contamination can rapidly damage precision piston, slipper and valve-interface surfaces.

5. Commission Gradually

After installation:

1. Confirm oil level.
2. Verify counter-clockwise rotation.
3. Confirm suction conditions.
4. Remove trapped air.
5. Run at low load.
6. Check leakage, noise and temperature.
7. Increase load progressively.

6. Perform 100% Simulated-Condition Testing

Recommended factory testing for a 172-5636 replacement unit includes:

• Rotation verification
• Flow testing
• Leakage inspection
• Variable-displacement response testing
• Pressure-response verification
• Continuous running testing
• Thermal stability testing
• Noise and vibration inspection

This provides a substantially stronger basis for confirming replacement reliability than a simple no-load functional check.

OEM Verification Reference

Primary source: Caterpillar official Parts Store entries for 172-5636 and 10R-8686.

Caterpillar officially confirms that:

• 172-5636 is a 22Cc Basic Slipper Piston Pump.
• Its displacement is 22 cm³/rev.
• Its specified rotation is counter-clockwise.
• Its material is carbon steel.
• Published dimensions are 10.8 in length × 10.0 in height.
• Compatible models listed for 172-5636 are D11R and D11T.
• 10R-8686 is shown as the Cat Reman alternative for 172-5636.
• The current dedicated 10R-8686 listing identifies D11R as its compatible model.