Dorman M390276 Brake Master Cylinder

Reliable Brake Master Cylinder for Buick, Chevrolet, Oldsmobile, and Pontiac

The Dorman M390276 Brake Master Cylinder is engineered to restore proper brake hydraulics in select Buick, Chevrolet, Oldsmobile, and Pontiac models. Designed with precision, this master cylinder ensures consistent brake fluid pressure for safe and responsive braking performance.

• Master cylinder bore diameter of 0.875 inches for accurate fluid displacement
• Durable aluminum construction for corrosion resistance and long service life
• Includes reservoir for brake fluid storage and monitoring
• Equipped with a sensor to support brake system diagnostics
• Two outlet ports with rearward outlet size M10 x 1.0 and 10mm secondary outlet thread diameter

Detailed Product Features and Specifications

The Dorman M390276 master cylinder is crafted from aluminum, providing a lightweight yet robust component that resists corrosion and wear. Its 0.875-inch bore diameter is designed to match OEM specifications, ensuring proper hydraulic pressure and pedal feel. The included reservoir allows for efficient brake fluid management, while the integrated sensor supports vehicle brake system monitoring. Featuring two outlets, including a rearward outlet sized M10 x 1.0 with a 1.0 thread pitch, this master cylinder is compatible with brake lines requiring these specific fittings.

Compatible Vehicles and Applications

This brake master cylinder is compatible with a range of vehicles, including Buick Achieva, Chevrolet Cavalier and Corsica, Oldsmobile Cutlass Calais, and Pontiac Grand Am, Skylark, and Sunbird models. The Dorman M390276 is designed to meet the hydraulic requirements of these vehicles, making it a suitable replacement part for brake system repairs and maintenance.

Common Brake System 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
• Brake system failure caused by internal seal deterioration

Installation Notes and Tips

When installing the Dorman M390276 master cylinder, ensure the brake system is properly bled to remove air and maintain hydraulic integrity. Verify that the reservoir is filled with the correct brake fluid type recommended for your vehicle. Since mounting hardware is not included, retain or source the necessary components for secure installation. Check all outlet fittings for proper thread engagement and torque specifications to prevent leaks.

Quality Assurance and Warranty Information

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 brake system performance. While specific warranty details are not provided here, Dorman typically offers limited warranties on their replacement parts to ensure customer confidence and product durability.