Dorman M98964 Brake Master Cylinder

Reliable Brake Master Cylinder for Jeep CJ5, CJ7, and Scrambler

The Dorman M98964 brake master cylinder is designed to restore proper brake hydraulics in Jeep CJ5, CJ7, and Scrambler models. Engineered with durable cast iron and a built-in reservoir, this master cylinder ensures consistent brake fluid delivery for safe and effective braking performance.

• Master cylinder bore diameter: 1 inch
• Constructed from durable cast iron material
• Includes an integrated reservoir for brake fluid
• Two outlet ports for brake line connections
• Rearward outlet size: 1/2-20 thread
• Secondary outlet thread diameter: 9/16-18
• Compatible with Jeep CJ5, CJ7, and Scrambler models

Durable Construction and Precise Specifications

The Dorman M98964 brake master cylinder features a robust cast iron body that withstands the rigors of daily driving and harsh conditions. Its 1-inch bore diameter is designed to provide the correct hydraulic pressure for the braking system in Jeep CJ5, CJ7, and Scrambler vehicles. The integrated reservoir simplifies brake fluid management, while the two outlet ports with specified thread sizes (1/2-20 rearward and 9/16-18 secondary) ensure proper fitment with existing brake lines. This master cylinder is supplied as a complete unit, ready to replace the original part and restore brake system functionality.

Applications and Common Issues Addressed

• Restores brake pressure loss due to worn or leaking master cylinder
• Eliminates spongy or unresponsive brake pedal feel
• Replaces master cylinder with damaged or corroded cast iron body
• Resolves brake fluid leaks from the reservoir or outlet ports
• Ensures proper brake fluid distribution in Jeep CJ5, CJ7, and Scrambler models

Installation Notes and Tips

When installing the Dorman M98964 brake master cylinder, ensure the brake system is properly bled to remove air and maintain hydraulic integrity. Verify thread compatibility with existing brake lines using the specified outlet sizes. Since mounting hardware is not included, retain or source appropriate fasteners for secure installation. Inspect all brake components during replacement to ensure overall system reliability.

Quality Assurance and Warranty Information

Dorman manufactures the M98964 brake master cylinder to meet or exceed OEM standards for fit, form, and function. The cast iron construction and precise machining contribute to long service life. While specific warranty details are not provided here, Dorman typically offers limited warranties on their brake hydraulics products to cover defects in materials and workmanship.