Dorman M39355 Brake Master Cylinder

Reliable Brake Master Cylinder for Cadillac and Oldsmobile

The Dorman M39355 brake master cylinder is engineered to restore proper brake hydraulics in select Cadillac and Oldsmobile vehicles. Designed specifically for models like the Eldorado, Seville, and Toronado, this master cylinder ensures consistent brake fluid pressure and reliable stopping power.

• Compatible with Cadillac Eldorado, Seville, and Oldsmobile Toronado
• Cast iron construction for durability and strength
• Includes reservoir for brake fluid storage
• Dual outlet design with rearward outlet size 1/2-20 and secondary outlet thread diameter 9/16-18
• Master cylinder bore diameters of 24.4 mm and 36 mm for precise hydraulic control
• Part number M39355 for exact replacement

Product Features and Specifications

This Dorman brake master cylinder features a cast iron body that provides long-lasting performance under demanding conditions. It includes a reservoir to hold brake fluid, eliminating the need for a separate component. The unit has two outlets, with a rearward outlet size of 1/2-20 and a secondary outlet thread diameter of 9/16-18, designed to fit the brake lines of the specified vehicles. The dual bore diameters of 24.4 mm and 36 mm allow for proper hydraulic pressure distribution, essential for safe braking operation.

Application and Common Repair Uses

This master cylinder is intended for use in brake hydraulic systems of Cadillac Eldorado, Cadillac Seville, and Oldsmobile Toronado models. It addresses issues such as:

• Brake pedal sinking or sponginess due to internal leaks
• Loss of hydraulic pressure affecting braking performance
• Brake fluid reservoir damage or leaks
• Corrosion or wear in the master cylinder bore
• Inconsistent brake pedal feel or travel

Installation Notes and Tips

Installation requires proper brake system bleeding to remove air and ensure optimal hydraulic function. Mounting hardware is not included, so existing hardware should be inspected and replaced if necessary. Verify compatibility with your vehicle’s brake line fittings, especially the outlet thread sizes. It is recommended to inspect related brake components during installation for a comprehensive brake system repair.

Quality Assurance and Warranty

Dorman parts are manufactured to meet or exceed OEM standards for fit and function. The M39355 brake master cylinder undergoes quality checks to ensure durability and performance. Please refer to Dorman’s warranty policy for specific coverage details.