Dorman M39661 Brake Master Cylinder

Reliable Brake Master Cylinder for Mercedes-Benz Models

The Dorman M39661 brake master cylinder is engineered for select Mercedes-Benz vehicles, including the 300D, 300TD, 380SE, 380SEC, 380SEL, 380SL, and 380SLC. Designed to restore proper brake hydraulics, this master cylinder ensures consistent brake fluid pressure and reliable stopping power.

• Compatible with Mercedes-Benz 300D, 300TD, 380SE, 380SEC, 380SEL, 380SL, and 380SLC
• Master cylinder bore diameters: 0.75 inch and 0.938 inch
• Constructed from durable cast iron for long-lasting performance
• Includes three outlets with a rearward outlet size of M10 x 1.0 and thread pitch of 1.0
• Does not include mounting hardware or reservoir
• Part number M39661 for precise identification and fitment

Product Details and Specifications

The Dorman M39661 brake master cylinder features dual bore diameters of 0.75 and 0.938 inches, accommodating the hydraulic requirements of specific Mercedes-Benz brake systems. Manufactured from cast iron, this master cylinder offers strength and resistance to wear under high-pressure conditions. It includes three outlets, with a secondary outlet thread diameter of 10 mm and a rearward outlet thread size of M10 x 1.0, ensuring compatibility with original brake lines. Note that this unit does not come with a reservoir or mounting hardware, so these components must be sourced separately if needed.

Common Applications and Problem Resolution

• Restores brake fluid pressure in Mercedes-Benz 300D and 300TD brake systems
• Addresses brake pedal sinking or sponginess due to master cylinder wear
• Eliminates brake fluid leaks from a failing master cylinder
• Resolves inconsistent braking performance in 380SE, 380SEC, 380SEL, 380SL, and 380SLC models
• Prevents brake system failure caused by internal seal deterioration

Installation Notes and Tips

When installing the Dorman M39661 brake master cylinder, ensure the brake system is properly bled to remove air and maintain hydraulic integrity. Since mounting hardware and reservoir are not included, verify compatibility and condition of existing components before installation. Use thread sealant or appropriate fittings on the M10 x 1.0 outlets to prevent leaks. Follow manufacturer torque specifications to avoid damage to the cast iron housing.

Quality Assurance and Warranty Information

Dorman brake master cylinders undergo rigorous testing to meet or exceed OEM standards for fit, form, and function. The M39661 part is backed by Dorman's limited warranty, providing coverage against defects in material and workmanship. This ensures dependable performance and peace of mind when replacing critical brake hydraulics on your Mercedes-Benz vehicle.