Dorman M39012 brake master cylinder for the 1982-1987 Dodge B350 and other vehicles turns pedal force into hydraulic pressure for the brakes. This new Dorman brake master cylinder comes with its reservoir.
- Part of the Dorman First Stop line
- Cast iron cylinder housing
- All rubber components are EPDM compound, which resists glycol-based brake fluid
- Made entirely of new materials
- Built to meet SAE International standards
Quick facts
- Part: Dorman M39012 brake master cylinder
- Fits: 1982-1987 Dodge B350 and other vehicles
- Material: Cast iron
- Condition: New
A brake pedal that feels soft or slowly sinks, or fluid showing around the cylinder body, can mean the master cylinder is worn. If it is the cause, this one replaces it. Before you order, look over the cylinder, the lines at its outlets and the reservoir with the engine off for wet spots or a falling fluid level, because a leak elsewhere in the system can feel the same.
Fits
It is a direct-fit replacement for the 1982-1987 Dodge B350, the 1982-1983 Plymouth PB350 and the 1975-1976 Chevrolet P30, with one cylinder per vehicle. If yours is not named here, find it in the "Vehicles it fits" section.
Specifications
Fit and size
- Quantity per vehicle: 1
- Bore diameter: 1.313 in
- Number of outlets: 2
- Secondary outlet thread diameter: 1/2-20 in
Build and materials
- Material: Cast iron
- Rubber components: EPDM compound
- Standards: SAE International
- Condition: New
- Country of origin: China
In the box
One master cylinder with its reservoir. Mounting hardware and a sensor are not included, so plan on new bolts, as the old ones may not be reusable.
Interchange: 83-46001 · 100-2703 · M-88001 · 13-1583 · 10-1583 · 130.68001 · 355-47203
18M68 · M900228 · 11583 · 4031345 · MC250330 · 6259173 · MC39012 · F84058 · MC84058
This part cross-references / interchanges with the following part numbers:
18M68, 83-46001, M900228, 100-2703, M-88001, 11583, 13-1583, 10-1583, 130.68001, 4031345, MC250330, 355-47203, 6259173, MC39012, F84058, MC84058
Frequently Asked Questions
Does the Dorman M39012 work as a brake master cylinder for a 1975-1976 Chevy P30?
Yes. The Dorman M39012 is listed for the 1975-1976 Chevrolet P30, which takes one. Other vehicles are in the "Vehicles it fits" section.
Is the reservoir included with the Dorman M39012 brake master cylinder?
Yes. The Dorman M39012 includes the reservoir. Mounting hardware and a sensor are not included.
What bore size and outlet thread does this brake master cylinder have?
The bore diameter is 1.313 in, and the cylinder has two outlets. The secondary outlet thread is 1/2-20 in.
Could a sinking pedal or fluid at the cylinder body mean the master cylinder is worn?
Yes, either sign can mean a worn master cylinder. A shop can test the system under pressure to confirm, since brake work is safety-critical.
Are the rubber components in this Dorman master cylinder made for glycol-based brake fluid?
Yes. All rubber components are made of EPDM compound, which resists glycol-based brake fluid.
