Dorman - First Stop Brake Master Cylinder P/N:M39324

Turn brake-pedal effort into the hydraulic pressure that operates the wheel brakes with the Dorman - First Stop Brake Master Cylinder (M39324). It installs as a direct-fit replacement for the 1981-1991 Chevrolet and GMC C-, K-, R- and V-series pickups and Suburbans listed below, all built with new — not remanufactured — materials for a dependable rebuild of the hydraulic supply.

• Cast iron housing: constructed to match the casting material of the original part for similar performance.
• EPDM rubber components: made of a high-quality EPDM compound for resistance to glycol-based brake fluid.
• 100% new: made entirely of new materials, not remanufactured, and produced to meet rigorous SAE International standards.
• Key specs: cast iron master cylinder, 1.25 in bore, two outlets, secondary outlet thread 1/2-20; reservoir included; sensor not included; mounting hardware not included.

The master cylinder generates the hydraulic pressure that pushes fluid to the brake circuits when you press the pedal. Signs this part may need replacing include a pedal that slowly sinks or feels spongy and external fluid seepage at the cylinder or reservoir. Diagnose the cause before replacing; if a failed master cylinder is the source, this unit replaces it. Mounting hardware is not included — consult the vehicle service information for the correct fasteners and whether they may be reused. Country of origin: China.

Fitment (see the Buyer's Guide tab for the full list): 1981-1986 Chevrolet C10 Suburban, C20, C20 Suburban, K10 Suburban, K20, K20 Suburban [All]; 1987-1988 Chevrolet R20, R20 Suburban [All]; 1987 Chevrolet V20 [All]; 1987-1988 Chevrolet V20 Suburban [All]; 1989 Chevrolet R2500 [All]; 1989-1991 Chevrolet R1500 Suburban, R2500 Suburban, V1500 Suburban, V2500 Suburban [All]; 1981-1986 GMC C1500 Suburban, C2500, C2500 Suburban, K1500 Suburban, K2500, K2500 Suburban [All]; 1987-1991 GMC R1500 Suburban, R2500 Suburban, V1500 Suburban, V2500 Suburban [All]; 1987-1989 GMC R2500 [All]; 1987 GMC V2500 [All].

Interchange: 174-599, 174599 · 18M169 · 783-44013, 78344013 · 83-44013, 8344013 · M900369 · 100-2591, 1002591 · M-86013, M86013 · 11872 · 11989 · 13-1872, 131872 · 10-1872, 101872 · 130.66013 · 131.66013 · MC104464 · 355-48002, 35548002 · 18008068 · 18010748 · 18014705 · 104464 · M1872 · NM1872 · 2539324 · MC39324 · F104464. Manufacturer part number M39324.