Dorman M390326 Brake Master Cylinder

Reliable Brake Master Cylinder for Chevrolet, Geo, and Suzuki

The Dorman M390326 Brake Master Cylinder is engineered to restore proper brake hydraulics in Chevrolet Sidekick, Geo Tracker, and Suzuki X-90 models. Designed with precision, this master cylinder ensures consistent brake fluid pressure for safe and effective braking performance.

• Master cylinder bore diameter: 0.938 inches for accurate fluid displacement
• Constructed from durable aluminum material for corrosion resistance
• Includes reservoir for brake fluid storage
• Equipped with a sensor to monitor brake system status
• Two outlets with rearward outlet size M10 x 1.0 and thread pitch 1.0
• Secondary outlet thread diameter of 10 mm
• Package contains the master cylinder only; mounting hardware not included

Technical Details and Compatibility

This Dorman brake master cylinder features a 0.938-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 part's service life. The included reservoir allows for proper brake fluid containment, while the integrated sensor provides feedback to the vehicle’s brake system for enhanced safety monitoring. With two outlets and a rearward outlet size of M10 x 1.0, this master cylinder is designed to fit the brake hydraulics of Chevrolet Sidekick, Geo Tracker, and Suzuki X-90 models precisely. The thread pitch of 1.0 ensures secure connections with compatible brake lines.

Common Applications and Problem Resolution

• Restores brake fluid pressure in vehicles experiencing spongy or unresponsive brakes
• Replaces leaking or damaged master cylinders causing brake fluid loss
• Addresses brake warning light activation due to sensor or hydraulic failure
• Improves brake pedal feel and responsiveness in Chevrolet Sidekick, Geo Tracker, and Suzuki X-90
• Solves issues related to brake fluid reservoir leaks or contamination

Installation Notes and Tips

Installation of the Dorman M390326 master cylinder requires careful attention to brake line connections and proper bleeding of the brake system to remove air. Since mounting hardware is not included, retain original hardware or source compatible fasteners. Verify thread pitch and outlet sizes to ensure correct fitment. It is recommended to inspect brake lines and related components during installation for wear or damage.

Quality Assurance and Warranty

Dorman parts are manufactured to meet or exceed OEM specifications, providing reliable performance and durability. The M390326 master cylinder includes a sensor to maintain system integrity and is backed by Dorman’s quality standards. Please refer to Dorman’s official warranty policy for coverage details.