Raybestos MC390981 Brake Master Cylinder

Reliable Brake Master Cylinder for Chevrolet and Pontiac Models

The Raybestos Element3; New Brake Master Cylinder MC390981 is engineered to restore precise brake hydraulics for Chevrolet Cobalt, Pontiac G5, and Pursuit vehicles. Designed with durable aluminum construction and exact fitment specifications, this master cylinder ensures consistent braking performance.

• Constructed from lightweight, corrosion-resistant aluminum
• Two mounting holes with 0.354-inch diameter for secure installation
• 0.875-inch bore size optimized for hydraulic pressure control
• Primary port thread size M10x1 and secondary port thread size M12x1 for compatibility with brake lines
• Compatible with Chevrolet Cobalt, Pontiac G5, and Pursuit models

About the Raybestos Element3; New Product Line

The Element3; New line from Raybestos focuses on delivering reliable brake hydraulics components with precise engineering and material quality. This brake master cylinder MC390981 is part of that line, offering a balance of durability and performance through its aluminum body and exact port threading, designed to meet OEM specifications for select GM vehicles.

Detailed Product Description and Specifications

This brake master cylinder features a 0.875-inch bore size, which is critical for maintaining proper hydraulic pressure within the braking system. The aluminum material provides resistance to corrosion and reduces overall weight compared to traditional cast iron units. With two mounting holes measuring 0.354 inches in diameter, the unit ensures a secure fit. The primary and secondary port threads (M10x1 and M12x1 respectively) allow for proper connection to brake lines, ensuring leak-free operation.

Common Applications and Problem Resolution

• Restores brake pressure loss in Chevrolet Cobalt and Pontiac G5 brake systems
• Replaces worn or leaking master cylinders causing brake fluid leaks
• Addresses spongy or unresponsive brake pedal issues
• Corrects inconsistent brake pedal travel or sinking
• Improves overall brake system reliability in Pontiac Pursuit vehicles

Installation Notes and Tips

Ensure the mounting holes align precisely with the vehicle’s brake booster or firewall. Verify the port thread sizes (M10x1 primary and M12x1 secondary) match the brake line fittings to avoid leaks. Bleed the brake system thoroughly after installation to remove air and restore proper hydraulic pressure. Use appropriate brake fluid as specified by the vehicle manufacturer.

Quality Assurance and Warranty Information

Raybestos manufactures the Element3; New MC390981 brake master cylinder to meet or exceed OEM standards. The aluminum construction and precise machining contribute to long service life and reliable performance. Warranty details should be confirmed with the product documentation or manufacturer.