Keep braking force reaching the shoes with this Dorman drum brake wheel cylinder, part number W37967 from the First Stop line. It converts hydraulic pressure from the master cylinder into the push that presses the rear brake shoes against the drum. It fits many vehicles, among them the 2002-2007 Chevrolet Trailblazer, 1992-2002 Chevrolet S10 and 1992-2002 GMC Sonoma. See the "Vehicles it fits" section for the full list and engine details.
- Direct replacement: Engineered as a direct match for the original drum brake wheel cylinder on the listed applications, in fit, function and performance.
- Cost-effective service: Replacing the cylinder while the drum brakes are already apart handles the hydraulic side of the job at the same time.
- Quality materials: Built with high-quality EPDM rubber cups and boots.
- Professionally tested: The wheel cylinder bores are surface-tested for an optimum sealing surface for the pressure cups, and the cylinder is manufactured and tested for quality assurance.
A wheel cylinder may need replacing if you see signs such as brake fluid seeping inside the drum or at the backing plate, fluid-soaked shoes, a soft or sinking pedal, or the vehicle pulling to one side. If a leaking cylinder is the cause, W37967 replaces it. Replacing the cylinders on both sides of the axle together is recommended for balanced braking. Bleed the brake system after installation.
Interchange: 784-44023 · 84-44023 · 101-1654 · W-86023 · 134.66023 · 135.66023 · 375-47075
78444023 · 8444023 · 1011654 · W86023 · 13466023 · 13566023 · 37547075 · 18E379 · W906712 · 34082 · WC14082 · 18017570 · 18060160 · 19213357 · 8180175700 · 8180601600 · WC37967 · F122222 · WC122222
This part cross-references / interchanges with the following part numbers:
18E379, 784-44023, 84-44023, W906712, 101-1654, W-86023, 34082, 134.66023, 135.66023, WC14082, 375-47075, 18017570, 18060160, 19213357, 8180175700, 8180601600, WC37967, F122222, WC122222
Frequently Asked Questions
What does a drum brake wheel cylinder do?
When you press the pedal, it converts hydraulic pressure from the master cylinder into force that pushes the drum brake shoes outward against the drum.
Does the Dorman W37967 fit the 2002-2007 Chevrolet Trailblazer?
Yes. It is a direct-fit rear wheel cylinder for the 2002-2007 Chevrolet Trailblazer, 1992-2002 Chevrolet S10 and 1992-2002 GMC Sonoma. See the "Vehicles it fits" section for other listed vehicles.
What are the cups and boots made of?
The cups and boots are high-quality EPDM rubber. The cylinder bores are surface-tested to give the pressure cups an optimum sealing surface.
What are signs a wheel cylinder may need replacing?
Signs include fluid seeping inside the drum or at the backing plate, fluid-soaked shoes, a soft pedal, or pulling to one side. Diagnose the cause before you replace parts.
What should I know about installing it?
It replaces the original cylinder during drum brake service. Bleed the brakes afterward, and follow the service information for fasteners. Replacing both sides together is recommended.
