Product Overview

The Track Roller — also known as Bottom Roller or Lower Roller — is an essential undercarriage component installed beneath the track frame of Komatsu PC40-7 crawler excavators.

The roller supports the machine weight, maintains track chain alignment and ensures stable crawler movement during travelling and excavation operations.

For a compact excavator, the track roller is exposed to:

• Continuous loading
• Uneven terrain impact
• Soil and gravel abrasion
• Mud and water contamination

A worn or damaged track roller may cause:

• Track chain deviation
• Increased travelling vibration
• Abnormal crawler noise
• Uneven track wear
• Premature sprocket and idler wear

Our Komatsu PC40-7 track rollers are manufactured according to OEM-style drawings, providing reliable aftermarket replacement solutions for mini excavator dealers, rental fleets and repair workshops.

Key Features & Benefits

Wide Compatibility

Designed for:

• Komatsu PC40-7
• Komatsu PC40-6
• Komatsu PC45-1
• Komatsu PC50UU series

Reference OEM numbers:

• 20T-30-00070
• 20T-30-00171
• 20T-30-00172
• 20T-30-00173
• 20T-30-00041

Compact Excavator Heavy-Duty Design

Although used on mini excavators, the roller is manufactured with:

• High-strength steel body
• Precision machining
• Reinforced sealing structure

Suitable for:

• Construction contractors
• Landscaping companies
• Agricultural applications
• Equipment rental fleets

High Strength Alloy Steel Construction

Manufactured from:

40Mn2 Alloy Steel

Advantages:

• Good wear resistance
• Strong impact resistance
• Stable performance under repeated loading

Heat Treatment Technology

The roller tread surface is hardened:

• Surface hardness: HRC 50-58
• Hardening depth: 4mm-8mm

Improves resistance against:

• Soil abrasion
• Gravel impact
• Daily operating wear

Reliable Seal System

Equipped with:

• Floating oil seal
• High-quality bushing
• Lifetime lubrication

Designed to prevent:

• Grease leakage
• Dust entry
• Water contamination

OEM-Style Replacement

Manufactured with:

• Accurate roller diameter
• Correct shaft dimensions
• Standard mounting structure

Provides direct bolt-on replacement without modification.

Technical Specifications

Why Trust Our Undercarriage Solutions?

For mini excavators like Komatsu PC40-7, reliable undercarriage components help maintain machine performance and reduce maintenance frequency.

A quality track roller helps:

• Maintain track alignment
• Reduce vibration
• Extend track chain service life
• Improve travelling stability
• Reduce operating costs

Every roller produced by our factory undergoes strict inspection:

• Raw material inspection
• Heat treatment verification
• Dimensional accuracy checking
• Seal performance testing

With professional manufacturing capability for excavator undercarriage parts, we provide OEM-compatible replacement solutions with stable quality, competitive pricing and warranty support.

Contact us with your machine model, serial number, OEM part number and roller position to confirm the correct replacement.