Raybestos MC391505 Brake Master Cylinder

Reliable Brake Master Cylinder for BMW Models

The Raybestos Element3; New Brake Master Cylinder MC391505 is engineered to restore precise brake hydraulics for various BMW vehicles. Designed with durable aluminum construction and specific mounting features, this master cylinder ensures consistent braking performance for your BMW 228i, 330i, 335i, and other compatible models.

• Constructed from lightweight, corrosion-resistant aluminum
• Two mounting holes with 0.346-inch diameter for secure installation
• 1.000-inch bore size optimized for brake fluid pressure control
• Two ports with M12x1 thread size for primary and secondary brake lines
• Compatible with a wide range of BMW models including 320i, 428i, and M240i

About the Raybestos Element3; New Product Line

The Element3; New line from Raybestos focuses on delivering reliable brake hydraulics components with modern materials and precise engineering. This brake master cylinder MC391505 benefits from the Element3; New design philosophy, offering enhanced durability and fitment accuracy for BMW vehicles. The aluminum master cylinder material reduces weight while maintaining strength, contributing to overall vehicle performance and safety.

Technical Details and Compatibility

This brake master cylinder features a 1.000-inch bore size, which is critical for maintaining proper hydraulic pressure in the braking system. The two mounting holes, each with a diameter of 0.346 inches, ensure a secure and stable fit. Both the primary and secondary ports use M12x1 thread sizes, compatible with standard brake line fittings on BMW models such as the 228i xDrive, 330i xDrive, 335i GT xDrive, and 440i Gran Coupe xDrive. The part number MC391505 corresponds specifically to this configuration, making it a precise replacement for your vehicle’s brake hydraulics.

Common Issues Addressed by This Brake Master Cylinder

• Brake pedal sinking or sponginess due to master cylinder wear
• Brake fluid leaks around the master cylinder ports or mounting area
• Inconsistent brake pressure affecting stopping performance
• Failure of the original master cylinder causing brake warning lights
• Corrosion or damage to the master cylinder body impacting brake system integrity

Installation Notes and Tips

When installing the Raybestos MC391505 brake master cylinder, ensure the mounting holes align precisely with the vehicle’s brake booster or firewall. Use the correct torque specifications for mounting bolts to avoid leaks or misalignment. Bleed the brake system thoroughly after installation to remove air and restore proper hydraulic pressure. Verify that the M12x1 threaded ports are compatible with your brake lines and use appropriate sealing methods to prevent fluid leaks.

Quality Assurance and Warranty

Raybestos manufactures the MC391505 brake master cylinder to meet or exceed OEM standards for fit, form, and function. The aluminum construction provides corrosion resistance and long service life. This part is backed by Raybestos’ quality control processes, ensuring reliable performance in BMW brake systems. Warranty details are provided by Raybestos and typically cover defects in material and workmanship under normal use conditions.