Dorman M39808 Brake Master Cylinder

Reliable Brake Master Cylinder for Jeep CJ5 and CJ7

The Dorman M39808 brake master cylinder is designed specifically for Jeep CJ5 and CJ7 models, providing a durable and precise hydraulic braking solution. Crafted from cast iron with a 1.063-inch bore diameter, this master cylinder includes a reservoir to ensure consistent brake fluid supply.

Key Features of the Dorman M39808 Brake Master Cylinder

• Constructed from cast iron for strength and durability
• Includes reservoir for brake fluid management
• 1.063-inch master cylinder bore diameter for accurate hydraulic pressure
• Two outlet ports with rearward outlet size 1/2-20 and secondary outlet thread diameter 9/16-18
• Compatible with Jeep CJ5 and CJ7 brake hydraulic systems

Detailed Product Description

The Dorman M39808 brake master cylinder is engineered to meet the hydraulic braking requirements of Jeep CJ5 and CJ7 vehicles. Its cast iron construction offers resistance to wear and corrosion, ensuring long-term reliability. The 1.063-inch bore diameter is calibrated to provide consistent brake fluid pressure, which is critical for safe and responsive braking performance. This master cylinder features two outlets: a rearward outlet sized at 1/2-20 and a secondary outlet with a 9/16-18 thread diameter, allowing for proper connection to the brake lines. The included reservoir maintains an adequate supply of brake fluid, helping to prevent air intrusion and maintain system integrity. Note that mounting hardware is not included with this part.

Common Applications and Issues Addressed

• Replacement for worn or leaking brake master cylinders on Jeep CJ5 and CJ7
• Restores proper hydraulic pressure for improved brake pedal feel
• Eliminates brake fluid leaks caused by damaged or corroded master cylinders
• Prevents brake system failure due to reservoir fluid loss
• Addresses inconsistent braking caused by internal cylinder wear

Installation Notes and Tips

• Ensure compatibility with Jeep CJ5 and CJ7 models before installation
• Bleed the brake system thoroughly after installation to remove air
• Inspect brake lines and fittings for wear or damage during replacement
• Use proper tools to avoid damaging outlet threads (1/2-20 rearward and 9/16-18 secondary)
• Check brake fluid level regularly after installation to maintain optimal performance

Quality Assurance and Warranty Information

Dorman manufactures the M39808 brake master cylinder to meet or exceed OEM specifications for Jeep CJ5 and CJ7 vehicles. The cast iron material and precise bore diameter contribute to consistent braking performance and durability. While specific warranty details are not provided, Dorman products typically come with a limited warranty covering defects in materials and workmanship. Refer to Dorman's official documentation for exact warranty terms.