Dorman M630655 Brake Master Cylinder

Reliable Brake Master Cylinder for Chevrolet Cobalt and Pontiac G5

The Dorman M630655 brake master cylinder is engineered to restore proper brake hydraulics for Chevrolet Cobalt and Pontiac G5 models. Designed with precision, this master cylinder ensures consistent brake fluid pressure and reliable stopping power.

• Master cylinder bore diameter: 0.875 inches for accurate fluid displacement
• Constructed from durable aluminum material for corrosion resistance
• Includes reservoir for brake fluid storage
• Equipped with sensor to monitor brake fluid levels
• Two outlet ports with rearward outlet size M10 x 1.0 and secondary outlet thread diameter M12 x 1.0

Product Details and Specifications

The Dorman M630655 brake master cylinder features a 0.875-inch bore diameter, which is critical for maintaining the correct hydraulic pressure in the brake system. Its aluminum construction offers strength and resistance to corrosion, extending the service life of the component. This master cylinder comes with an integrated reservoir and sensor, allowing for efficient brake fluid management and monitoring. The two outlets provide proper fluid distribution, with precise thread sizes (M10 x 1.0 rearward outlet and M12 x 1.0 secondary outlet) to ensure secure connections within the brake hydraulic system.

Compatible Vehicles and Applications

This brake master cylinder is compatible with Chevrolet Cobalt and Pontiac G5 vehicles, making it a suitable replacement part for brake hydraulic repairs on these models. The part number M630655 corresponds specifically to these applications, ensuring proper fit and function.

• Restores brake fluid pressure for consistent braking performance
• Replaces worn or leaking master cylinders causing brake fluid loss
• Addresses brake pedal issues such as sponginess or sinking
• Resolves sensor-related brake fluid warnings
• Prevents brake system failure due to master cylinder malfunction

Installation Notes and Tips

When installing the Dorman M630655 brake master cylinder, ensure the brake fluid reservoir is properly filled and free of contaminants. Bleed the brake system thoroughly to remove air pockets and verify that all outlet connections match the specified thread sizes (M10 x 1.0 and M12 x 1.0). Use appropriate tools to avoid damaging the aluminum housing or sensor components. This part does not include mounting hardware, so retain original fasteners or acquire compatible replacements as needed.

Quality Assurance and Warranty

Dorman manufactures this brake master cylinder to meet or exceed OEM standards for fit, form, and function. The aluminum construction and integrated sensor contribute to reliable operation under normal driving conditions. While specific warranty details are not provided, Dorman products typically come with a limited warranty covering defects in materials and workmanship.