Dorman M39357 Brake Master Cylinder

Reliable Brake Master Cylinder for Ford F-100 and F-150

The Dorman M39357 Brake Master Cylinder is engineered to restore proper brake hydraulics in Ford F-100 and F-150 trucks. Designed with durable cast iron and a 1-inch bore diameter, this master cylinder ensures consistent brake fluid pressure for safe stopping performance.

• Compatible with Ford F-100 and F-150 models
• Master cylinder bore diameter: 1 inch
• Constructed from durable cast iron material
• Includes reservoir for brake fluid
• Two outlet ports with rearward outlet size 1/2-20 and secondary outlet thread diameter 7/16-24
• Package contains the master cylinder only; mounting hardware not included

Product Details and Specifications

The Dorman M39357 master cylinder features a cast iron body designed to withstand the rigors of brake system pressure and heat. Its 1-inch bore diameter is optimized for the hydraulic requirements of Ford F-100 and F-150 brake systems. This unit includes a reservoir to hold brake fluid, facilitating proper fluid delivery and pressure maintenance. The master cylinder has two outlets: a rearward outlet sized at 1/2-20 and a secondary outlet with a 7/16-24 thread diameter, ensuring compatibility with the brake lines on these Ford models. Note that mounting hardware is not included, so existing hardware or separate purchase may be necessary.

Common Applications and Problem Resolution

• Replaces worn or leaking master cylinders causing brake fluid loss
• Restores proper hydraulic pressure for improved brake pedal feel
• Addresses spongy or unresponsive brake pedal issues
• Fixes internal seal failures leading to brake system leaks
• Resolves brake fluid reservoir damage or contamination

Installation Notes and Tips

When installing the Dorman M39357 master cylinder on Ford F-100 or F-150 trucks, ensure the brake system is properly bled to remove air and maintain hydraulic integrity. Verify that the outlet thread sizes match the brake line fittings to avoid leaks. Since mounting hardware is not included, inspect existing hardware for wear or damage and replace if necessary. Follow manufacturer torque specifications to secure the master cylinder.

Quality Assurance and Warranty

Dorman manufactures the M39357 master cylinder to meet or exceed OEM standards for fit, form, and function. The cast iron construction provides durability and resistance to wear. While specific warranty details should be confirmed at the point of purchase, Dorman typically offers limited warranties covering defects in material and workmanship to ensure product reliability.