If a worn or leaking master cylinder is behind a soft or sinking brake pedal, the Dorman First Stop Brake Master Cylinder M630839 is a new replacement built to turn pedal effort into hydraulic pressure for the brakes. It is a direct-fit replacement for the 2011-2016 Chrysler Town & Country (All engines), the 2011-2020 Dodge Grand Caravan (All engines), and the 2012-2014 Ram C/V (All engines).
Dorman engineered this master cylinder to replicate the design, function, and performance of the original unit on the listed vehicles. It uses new, high-quality materials for a safe, durable replacement.
- Precise replacement: The aluminum housing is built to match the original part's material for similar performance.
- Durable design: Every rubber component uses a high-quality EPDM compound that resists glycol-based brake fluid.
- 100% new: The unit is made entirely of new materials for quality and safety.
- Strict specifications: It is built to meet demanding SAE International standards.
Specifications: 1.063 in. bore diameter, two outlets, 7/16-24 rearward outlet size, and 7/16-24 secondary outlet thread diameter. The package contains one master cylinder. The reservoir, sensor, and mounting hardware are not included. Transfer or replace the reservoir and sensor as directed by the service procedure. Consult the vehicle service information for the correct fasteners and whether they may be reused. Country of origin: China.
Signs a master cylinder may need replacing: a soft or spongy pedal, a pedal that slowly sinks under steady pressure, or brake fluid leaking at the master cylinder. Diagnose the brake system before replacing parts, and bleed the system according to the service information after installation.
Interchange: 100-4026 · 10-4568 · 130.67050 · 355-40086
1004026 · 104568 · 13067050 · 35540086 · 4581491AA · 4581491AB · 4581491AC · 4581491AD · NM4318 · MC391424 · R144568
This part cross-references / interchanges with the following part numbers:
100-4026, 10-4568, 130.67050, 4581491AA, 4581491AB, 4581491AC, 4581491AD, 355-40086, NM4318, MC391424, R144568
Frequently Asked Questions
Which vehicles does the Dorman M630839 fit?
It is listed for the 2011-2016 Chrysler Town & Country, the 2011-2020 Dodge Grand Caravan, and the 2012-2014 Ram C/V, all engines. The "Vehicles it fits" section shows the full application list.
Does this master cylinder come with a reservoir?
No, the reservoir, sensor, and mounting hardware are not included. Transfer or replace the reservoir and sensor per the service procedure, and check the service information for the correct fasteners and whether they may be reused.
What are the bore size and outlet threads?
It has a 1.063-inch bore diameter and two outlets. The rearward outlet size is 7/16-24, and the secondary outlet thread diameter is 7/16-24.
What kind of brake fluid is it compatible with?
Its rubber components use an EPDM compound made to resist glycol-based brake fluid. Fill the system with the brake fluid type your vehicle's manufacturer specifies.
What are signs my master cylinder may need replacing?
Warning signs include a soft or spongy pedal, a pedal that sinks under steady pressure, or fluid leaking at the master cylinder. Other brake parts can cause these symptoms, so diagnose the system first.
