Dorman M39721 Brake Master Cylinder

Reliable Brake Master Cylinder for Mazda 323 and Mercury Tracer

The Dorman M39721 brake master cylinder is engineered to restore proper brake hydraulics in your Mazda 323 or Mercury Tracer. Designed with durable cast iron and a built-in reservoir, this master cylinder ensures consistent brake fluid delivery and reliable stopping power.

• Master cylinder bore diameter: 0.875 inches for precise hydraulic pressure
• Constructed from cast iron for strength and durability
• Includes reservoir for brake fluid storage
• Equipped with a sensor to monitor brake system status
• Two outlets with rearward outlet size M10 x 1.0 and thread pitch 1.0

Product Details and Specifications

The Dorman M39721 brake master cylinder features a cast iron body that withstands the rigors of brake system pressure and heat. Its 0.875-inch bore diameter is calibrated to provide accurate hydraulic force to the brake calipers or wheel cylinders. The included reservoir simplifies brake fluid management, while the integrated sensor supports vehicle brake system monitoring. This master cylinder has two outlets, including a secondary outlet with a 10 mm thread diameter, and a rearward outlet sized M10 x 1.0 with a 1.0 thread pitch, ensuring compatibility with the brake lines on Mazda 323 and Mercury Tracer models.

Compatible Vehicles and Applications

• Designed specifically for Mazda 323 brake hydraulic systems
• Compatible with Mercury Tracer brake systems requiring a 0.875-inch bore master cylinder
• Ideal replacement for worn or leaking master cylinders causing brake fluid loss or poor pedal feel
• Restores proper brake pressure and pedal responsiveness
• Addresses issues such as brake fluid leaks, spongy brake pedal, and brake warning light activation

Installation Notes and Tips

When installing the Dorman M39721 brake master cylinder, ensure the brake fluid reservoir is properly filled and free of contaminants. Bleed the brake system thoroughly to remove air and restore optimal hydraulic pressure. Note that mounting hardware is not included, so retain original fasteners or acquire appropriate replacements. Verify thread sizes and outlet fittings match your vehicle’s brake lines before installation.

Quality Assurance and Warranty

Dorman manufactures this brake master cylinder to meet or exceed OEM specifications for Mazda 323 and Mercury Tracer vehicles. The cast iron construction and integrated sensor contribute to reliable brake system performance. While specific warranty details are not provided here, Dorman products typically come with a limited warranty against defects in materials and workmanship.