Dorman M390371 Brake Master Cylinder

Reliable Brake Master Cylinder for Oldsmobile and Pontiac Vehicles

The Dorman M390371 brake master cylinder is designed specifically for select Oldsmobile and Pontiac models, including the Montana, Silhouette, and Trans Sport. This aluminum master cylinder features an integrated reservoir and sensor, providing a precise and dependable braking solution.

Key Features of the Dorman M390371 Brake Master Cylinder

• Master cylinder bore diameter: 1 inch for consistent hydraulic pressure
• Constructed from durable aluminum material for corrosion resistance
• Includes reservoir for brake fluid storage
• Equipped with a sensor to monitor brake system status
• Four outlet ports to support complex brake hydraulic systems
• Secondary outlet thread diameter: 10 mm
• Rearward outlet size: M10 x 1.0 thread and unthreaded for versatile installation
• Package contains the master cylinder only; mounting hardware not included

Detailed Product Description

The Dorman M390371 brake master cylinder is engineered to meet the specifications of Oldsmobile Montana, Pontiac Silhouette, and Pontiac Trans Sport models. Its 1-inch bore diameter ensures proper hydraulic pressure for effective braking performance. Made from aluminum, this master cylinder offers enhanced durability and resistance to corrosion compared to traditional materials. The included reservoir simplifies brake fluid management, while the integrated sensor provides real-time monitoring of brake system conditions. With four outlets and specific thread sizes, this master cylinder supports complex brake hydraulic configurations commonly found in these vehicle models.

Common Applications and Issues Addressed

• Restores proper brake fluid pressure in Oldsmobile Montana and Pontiac Silhouette brake systems
• Replaces worn or leaking master cylinders causing brake pedal sponginess
• Addresses brake fluid reservoir leaks or sensor malfunctions
• Supports brake system repairs requiring multiple outlet connections
• Improves brake system reliability in Pontiac Trans Sport vehicles

Installation Notes and Tips

• Ensure compatibility with Oldsmobile Montana, Pontiac Silhouette, and Pontiac Trans Sport models before installation
• Mounting hardware is not included; retain original hardware or source separately
• Bleed the brake system thoroughly after installation to remove air
• Verify sensor connections for proper brake system monitoring
• Inspect all brake lines and fittings for wear or damage during replacement

Quality Assurance and Warranty Information

Dorman manufactures the M390371 brake master cylinder to meet or exceed OEM standards for fit, form, and function. The aluminum construction and integrated sensor contribute to long-term reliability. While specific warranty details may vary, Dorman typically offers a limited warranty covering defects in materials and workmanship. Consult product documentation or the supplier for exact warranty terms.