Keep brake fluid moving to every wheel with the Dorman First Stop Brake Master Cylinder M39580, precision-engineered to replicate the original master cylinder's design, function and performance. It is listed for several models, all engines, among them the 1985-1990 Buick Electra, 1986-1990 Buick LeSabre and 1986-1990 Cadillac DeVille. See the Buyer's Guide tab for the full list.
The master cylinder converts pedal effort into hydraulic pressure for the brake system. This unit is made of high-quality materials and is designed as a safe, durable replacement.
- Precise replacement: the aluminum cylinder housing is constructed to match the original part's material and is intended to deliver similar performance.
- Durable design: all rubber components use a high-quality EPDM compound that resists glycol-based brake fluid.
- 100% new: made entirely from new materials for quality and safety.
- Strict specifications: built to meet rigorous SAE International standards.
Specifications: four outlets with M16 x 1.5 and M11 x 1.5 outlet threads, and bore diameters of 36 mm and 24 mm. The reservoir is included. A sensor and mounting hardware are not included, so consult the vehicle service information for the correct fasteners and whether the originals may be reused. Country of origin: China.
Signs this part may need replacing include a spongy or slowly sinking brake pedal, fluid leaking at the master cylinder, or a dropping fluid level. If a failed master cylinder is the cause, M39580 replaces it. Diagnose the brake system before replacing parts.
