Turn pedal effort into hydraulic pressure for your brakes with the Dorman First Stop Brake Master Cylinder, part number M39435. It fits many vehicles, among them the 1981-1996 Chevrolet P30, 1981-1996 GMC P3500 and 1989-1991 Chevrolet R3500, as a direct-fit replacement for the listed applications. See the Buyer's Guide tab for the full list.
Precision-engineered to mirror the design, function and performance of the original master cylinder on the listed applications, this unit is built from new, high-quality materials for a durable replacement.
- Precise replacement: The cast iron cylinder housing is built to match the casting material of the original part and is intended to deliver similar performance.
- Durable design: Every rubber component uses 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: 1.313 in. bore diameter, two outlets, 1/2-20 rearward outlet size, and reservoir included. Mounting hardware and a sensor are not included; consult the vehicle service information for the correct fasteners and whether the originals may be reused. Country of origin: China.
A spongy or sinking brake pedal, fluid leaks at the master cylinder or a steadily dropping fluid level are signs this part may need replacing. Diagnose the brake system before you replace parts.
Interchange: 174-838 · 783-44012 · 83-44012 · 100-2589 · M-86012 · 13-1982 · 10-1982 · 130.66012 · 131.66012 · 355-47145
174838 · 78344012 · 8344012 · 1002589 · M86012 · 131982 · 101982 · 13066012 · 13166012 · 35547145 · 18M230 · M900430 · 11982 · MC108145 · 14066425 · 108145 · M1982 · NM1982 · MC39435 · F108145
This part cross-references / interchanges with the following part numbers:
174-838, 18M230, 783-44012, 83-44012, M900430, 100-2589, M-86012, 11982, 13-1982, 10-1982, 130.66012, 131.66012, MC108145, 355-47145, 14066425, 108145, M1982, NM1982, MC39435, F108145
