Dorman M39012 Brake Master Cylinder

Reliable Brake Master Cylinder for Chevrolet, Dodge, and Plymouth

The Dorman M39012 brake master cylinder is engineered to restore proper brake hydraulics in Chevrolet B350, Dodge P30, and Plymouth PB350 vehicles. Designed with durable cast iron and a precise 1.313-inch bore diameter, this master cylinder ensures consistent braking performance.

• Master cylinder bore diameter: 1.313 inches for accurate hydraulic pressure
• Constructed from cast iron for strength and durability
• Includes reservoir for fluid storage and management
• Two outlets with rearward outlet size of 9/16-18 and secondary outlet thread diameter of 0.5 inches
• Package contains the master cylinder only; mounting hardware not included

Product Details and Specifications

The Dorman M39012 brake master cylinder is designed specifically for brake hydraulics systems requiring a 1.313-inch bore diameter. Its cast iron construction provides long-lasting resistance to wear and corrosion. The included reservoir allows for proper brake fluid containment, while the two outlets facilitate fluid distribution to the braking system. The rearward outlet size measures 9/16-18, and the secondary outlet thread diameter is 0.5 inches, ensuring compatibility with the brake lines on Chevrolet B350, Dodge P30, and Plymouth PB350 models. Note that this part does not include mounting hardware or sensors.

Compatible Vehicles and Applications

This brake master cylinder is compatible with the following vehicles:

• Chevrolet B350
• Dodge P30
• Plymouth PB350

Use the Dorman M39012 to replace worn or failing master cylinders in these models to maintain safe and effective braking performance.

Common Issues Addressed by This Master Cylinder

• Brake pedal sinking or sponginess due to internal leaks
• Loss of hydraulic pressure affecting braking efficiency
• Brake fluid reservoir leaks or contamination
• Uneven brake application between front and rear brakes
• Failure of the master cylinder bore causing brake system malfunction

Installation Notes and Tips

Installation of the Dorman M39012 brake master cylinder requires proper brake system bleeding to remove air and ensure optimal hydraulic pressure. Since mounting hardware is not included, verify compatibility with existing hardware or source appropriate components. Inspect brake lines and fittings for wear or damage during installation. Professional installation is recommended for safety and performance.

Quality Assurance and Warranty

Dorman manufactures the M39012 brake master cylinder to meet or exceed OEM specifications for durability and performance. The cast iron construction and precise bore diameter contribute to reliable brake system operation. Warranty details should be confirmed with the product documentation or supplier to ensure coverage.