Chevrolet Master Cylinder OEM CM116209

This Dorman master cylinder for Chevrolet delivers a firm, high pedal with fresh cup seals and a properly machined bore.

The brake master cylinder is the tandem hydraulic pump behind the pedal that converts pedal travel into line pressure. Internal cup seals fatigue over time, bypassing fluid past the piston and producing a pedal that slowly sinks to the floor with the engine running. A new master cylinder has fresh seals, a properly machined bore, and the right port geometry for direct line-fit connection. Bench-bleed before installing for the shortest possible on-vehicle bleed.

Verify your fitment with the year, make, model, and trim of your vehicle before ordering. If you are not sure, contact us with your VIN or vehicle configuration and we will match the correct part to your application before you buy.

Cross-Reference

Manufacturer part number CM116209. This is a Dorman catalog part. Confirm the OE reference for your vehicle matches before installing.

Why You Might Need This

A pedal that sinks slowly to the floor with the engine running is the classic internal cup-seal bypass failure. Fluid loss without an external leak points to the master cylinder. Bench-bleed the new master cylinder for the fastest possible pedal return.

Installation Notes

Bench-bleed the new master cylinder before installing it on the vehicle. Clamp the mounting flange gently in a vise, install the bleeder-hose fittings included with the master cylinder, and stroke the piston slowly until no more air comes out of the ports. This is the single fastest way to shorten the on-vehicle bleed procedure and get a firm pedal immediately.

Shipping and Returns

Free shipping on orders over $75. Same-day shipping on in-stock parts ordered before 2:00 PM CT weekdays. Orders placed after the same-day cutoff ship the next business day. Every order ships from our climate-controlled warehouse; parts do not sit outside where humidity and temperature swings could damage packaging.

30-day return window on unopened, unused parts in original packaging. Open parts installed without verified fitment: no return, or up to a 40 percent restocking fee depending on condition. Brake friction material (pads and shoes) is safety-critical and cannot be returned once a pad has touched a rotor. If a part does not fit your vehicle as described, we cover the return shipping and make it right.

This is a remanufactured unit sold with a core charge or core-return expectation. Return the original core to Core Brake Parts using the return label we send with your order to redeem the core credit.