Dorman M630275 brake master cylinder for the 2003-2004 Chevrolet C4500 Kodiak and other vehicles turns pedal force into hydraulic pressure for the brakes. Its housing material is chosen to match the original part's casting material for similar performance.
- Aluminum housing with a 40 mm bore diameter
- EPDM rubber components that resist glycol-based brake fluid
- Made entirely of new materials
- Built to meet SAE International standards
- Reservoir and sensor included with the cylinder
Quick facts
- Part: Dorman M630275 brake master cylinder
- Fits: 2003-2004 Chevrolet C4500 Kodiak and other vehicles
- Material: Aluminum
- Condition: New
A brake pedal that feels soft or sinks slowly, or fluid showing around the cylinder body, can mean the master cylinder is wearing out, though other brake parts can cause the same feel. With the engine off and cool, look for dampness around the cylinder body, the reservoir and the lines at the cylinder before you replace it. A shop can pressure-test the system.
Fits
This master cylinder fits the 2003-2004 Chevrolet C4500 Kodiak and the 2003-2004 GMC C4500 Topkick, and both take a single master cylinder.
Specifications
Fit and size
- Quantity per vehicle: 1
- Bore diameter: 40 mm
- Number of outlets: 2
- Secondary outlet thread diameter: 1/2-20 in
Build and materials
- Material: Aluminum
- Condition: New
- Reservoir: included
- Sensor: included
- Country of origin: China
In the box
One master cylinder with its reservoir and sensor. Mounting hardware is not included, so plan on new fasteners.
Interchange: 174-774 · 100-3029 · 13-3798 · 10-3798 · 130.66064 · 355-47190
15092396 · 18046692 · MC390850 · R135577
This part cross-references / interchanges with the following part numbers:
174-774, 100-3029, 13-3798, 10-3798, 130.66064, 355-47190, 15092396, 18046692, MC390850, R135577
Frequently Asked Questions
Does the Dorman M630275 master cylinder fit the 2003-2004 Chevrolet C4500 Kodiak?
Yes. Dorman M630275 fits the 2003-2004 Chevrolet C4500 Kodiak and the 2003-2004 GMC C4500 Topkick, one per vehicle.
Does this brake master cylinder come with the reservoir and sensor?
Yes. Dorman M630275 includes the reservoir and the sensor. Mounting hardware is not included.
What is the bore diameter of this brake master cylinder?
The bore diameter is 40 mm. The cylinder has two outlets, and the secondary outlet thread is 1/2-20 in.
Are the rubber parts in this master cylinder made for glycol-based brake fluid?
Yes. All rubber components are made of EPDM compound, which resists glycol-based brake fluid.
How can I tell if my master cylinder is leaking or failing?
Fluid around the cylinder body or a soft, sinking pedal can mean it is failing. Have brake problems looked at promptly; a shop can pressure-test the system.
