Dorman M630639 Brake Master Cylinder

Reliable Brake Master Cylinder for Chevrolet Aveo and Pontiac G3

The Dorman M630639 brake master cylinder is engineered to restore proper brake hydraulics in Chevrolet Aveo, Aveo5, Pontiac G3, and G3 Wave models. Designed with precision, this aluminum master cylinder includes a reservoir and sensor to ensure consistent brake performance.

• Master cylinder bore diameter: 0.875 inches for accurate hydraulic pressure
• Constructed from durable aluminum material for corrosion resistance
• Includes reservoir for fluid storage and sensor for monitoring brake system status
• Two outlets with rearward outlet size M10 x 1.0 and secondary outlet thread diameter 10 mm
• Thread pitch of 1.0 for secure fitting

Detailed Product Description

The Dorman M630639 brake master cylinder is a direct replacement part designed specifically for Chevrolet Aveo, Aveo5, Pontiac G3, and G3 Wave vehicles. Its aluminum construction provides strength and resistance to corrosion, extending the service life of the brake system. The included reservoir allows for proper brake fluid containment, while the integrated sensor helps maintain system integrity by monitoring fluid levels or pressure. With a bore diameter of 0.875 inches, this master cylinder delivers precise hydraulic pressure to the brake lines through its two outlets, featuring a rearward outlet size of M10 x 1.0 and a secondary outlet thread diameter of 10 mm. The 1.0 thread pitch ensures compatibility with OEM brake line fittings.

Common Brake Issues Addressed

• Brake pedal sinking or sponginess due to master cylinder wear
• Brake fluid leaks from a damaged or corroded master cylinder
• Inconsistent brake pressure affecting stopping performance
• Faulty brake fluid level sensor triggering warning lights
• Replacement needed after brake system overhaul or failure

Installation Notes and Tips

Installation of the Dorman M630639 brake master cylinder requires proper brake fluid handling and bleeding procedures to avoid air in the brake lines. Ensure the mounting surface is clean and free of debris before installation. Use compatible brake lines with M10 x 1.0 thread fittings to secure the outlets. Since mounting hardware is not included, retain original fasteners or acquire appropriate replacements. Verify sensor connections are properly seated to maintain brake system monitoring.

Quality Assurance and Warranty

Dorman manufactures the M630639 brake master cylinder to meet or exceed OEM specifications for Chevrolet Aveo and Pontiac G3 models. The aluminum construction and integrated sensor contribute to reliable brake system operation. While specific warranty details are not provided, Dorman products typically come with a limited warranty covering defects in materials and workmanship.