Dorman M390386 Brake Master Cylinder

Reliable Brake Master Cylinder for Chevrolet, Oldsmobile, and Pontiac

The Dorman M390386 Brake Master Cylinder is engineered to restore proper brake hydraulics in select Chevrolet, Oldsmobile, and Pontiac vehicles. Designed with precision, this master cylinder ensures consistent brake fluid pressure for safe and effective braking performance.

• Master cylinder bore diameter: 1 inch for accurate fluid displacement
• Constructed from durable aluminum material for corrosion resistance
• Includes reservoir for brake fluid storage
• Equipped with sensor to monitor brake system status
• Two outlets with rearward outlet size M10 x 1.0 and thread pitch 1.0
• Compatible with Chevrolet Malibu, Oldsmobile Alero, Cutlass, and Pontiac Grand Am

Product Details and Specifications

This Dorman brake master cylinder (part number M390386) features a 1-inch bore diameter, which is critical for maintaining the correct hydraulic pressure in the brake system. The aluminum construction offers strength and resistance to corrosion, extending the service life of the component. The included reservoir allows for proper brake fluid containment, while the integrated sensor provides real-time monitoring of brake fluid levels or pressure, depending on vehicle configuration. The master cylinder has two outlets, with a secondary outlet thread diameter of 10 mm and a rearward outlet size of M10 x 1.0, ensuring compatibility with the brake lines on Chevrolet Malibu, Oldsmobile Alero, Cutlass, and Pontiac Grand Am models. The thread pitch of 1.0 ensures secure fitting during installation.

Common Applications and Problem Resolution

• Restores brake fluid pressure in vehicles experiencing soft or spongy brake pedal feel
• Replaces leaking or damaged master cylinders causing brake fluid loss
• Addresses brake warning light activation related to master cylinder sensor issues
• Improves brake system responsiveness in Chevrolet Malibu, Oldsmobile Alero, Cutlass, and Pontiac Grand Am
• Solves brake pedal sinking or failure due to internal master cylinder wear

Installation Notes and Tips

Installation of the Dorman M390386 master cylinder requires proper brake system bleeding to remove air and ensure optimal hydraulic function. Mounting hardware is not included, so retain original fasteners or acquire appropriate replacements. Verify thread pitch and outlet sizes to match vehicle brake lines. Sensor connections should be carefully reattached to maintain brake system monitoring. It is recommended to inspect related brake components during installation for comprehensive brake system maintenance.

Quality Assurance and Warranty Information

Dorman manufactures this brake master cylinder to meet or exceed OEM specifications for fit, form, and function. The aluminum construction and integrated sensor contribute to reliable performance. While specific warranty details are not provided here, Dorman typically offers limited warranties on their brake hydraulics products. Consult product documentation or the manufacturer for exact warranty terms.