KOMATSU 421-33-11440 Seal Ring

Product Overview

The KOMATSU 421-33-11440 Seal Ring is a Genuine Komatsu OEM wet disc brake piston seal designed to provide a reliable hydraulic seal within the wheel brake assembly. The seal ring prevents hydraulic fluid leakage while maintaining the pressure required for proper brake piston operation, ensuring dependable braking performance, system efficiency, and long service life.

Manufactured to Komatsu’s OEM engineering standards, the 421-33-11440 Seal Ring delivers precise fit, excellent sealing performance, and durability under demanding construction, mining, quarrying, and heavy-duty hauling applications. It is designed as a direct OEM replacement, restoring the original performance and reliability of the wet disc brake system.

Key Features

• Genuine Komatsu OEM Seal Ring
• Part Number: 421-33-11440
• Wet disc brake piston seal
• Provides a reliable hydraulic seal within the brake assembly
• Helps maintain proper hydraulic pressure for consistent braking performance
• Prevents hydraulic fluid leakage and contamination
• Manufactured to Komatsu OEM specifications
• Direct OEM replacement
• Designed for durability and long service life
• Suitable for heavy-duty construction, mining, quarrying, and haulage equipment

Technical Specifications

Note: Komatsu has not publicly published additional specifications such as seal material, dimensions, operating pressure, temperature range, or weight for the 421-33-11440 Seal Ring. Always verify the correct part using the machine serial number and the official Komatsu Parts Catalog before ordering.

Application Information

The KOMATSU 421-33-11440 Seal Ring is a critical component of the machine’s wet disc brake system. Installed within the brake piston assembly, it creates a leak-free hydraulic seal that enables efficient brake actuation while protecting the brake assembly from contamination and hydraulic pressure loss.

Manufactured to Komatsu OEM standards, the seal ring is designed to withstand:

• Continuous hydraulic system pressure
• Brake actuation cycles
• Exposure to hydraulic oil
• Heavy vibration and shock loads
• High operating temperatures
• Construction, quarrying, mining, and heavy-haul operating environments

Proper installation and replacement of worn seals are essential to maintain safe braking performance and extend brake component service life.

Compatible Komatsu Equipment

The KOMATSU 421-33-11440 Seal Ring is used in the wet disc brake systems of various Komatsu machines, including:

Wheel Loaders

• WA400
• WA420
• WA450
• WA470
• WA500

Rigid Dump Trucks

• HD325
• HD405

Articulated Dump Trucks

• HM250
• HM300
• HM350
• HM400

Compatibility varies depending on the machine model, serial number, axle configuration, and production specification. Always verify compatibility before ordering using the machine identification information.

Additional Compatibility Information

The 421-33-11440 Seal Ring is a configuration-specific brake system component. Before installation, verify:

• Machine model
• Machine Serial Number
• Product Identification Number (PIN)
• Axle and brake assembly configuration
• Existing seal ring part number
• Brake system arrangement

Any modifications to the original machine configuration may affect compatibility. Verification through the official Komatsu Parts Catalog or an authorized Komatsu dealer is recommended before installation.

Benefits

Installing a genuine KOMATSU 421-33-11440 Seal Ring helps:

• Restore proper hydraulic sealing
• Maintain consistent brake performance
• Prevent hydraulic fluid leakage
• Protect internal brake components from contamination
• Extend brake system service life
• Reduce maintenance-related downtime
• Preserve original OEM braking performance
• Deliver OEM-quality fit, durability, and long-lasting reliability in demanding heavy-duty applications.