Parts / Master Cylinder
Used Master Cylinder for Medium-Duty Trucks
Brake master cylinders — the fix for the sinking pedal with no leak anywhere.
- Used OEM part
- Tested before shipping
- 30-day warranty
- Ships to the lower 48
A pedal that slowly sinks to the floor at a stop light, with a full reservoir and nothing wet, is a master cylinder bypassing internally. It’s the brake failure shops miss most often because there’s no visible leak — and a truck that has to be pumped to stop is a liability on every trip.
We stock used OEM master cylinders from running donor trucks, pressure-tested and checked for bore condition, in the correct bore size and port configuration for your VIN. For discontinued applications (Kodiak/TopKick, older N-series) a used OEM unit is often the only option with the right bore and thread pitch.
Signs your master cylinder has failed
- Pedal sinks slowly under steady pressure at a stop
- Soft pedal that pumps up, with no external leak
- Brake fluid on the booster face or inside the booster (rear seal)
- Reservoir level dropping with no visible leak — check the booster
- Fine cold, sinks when hot
- Brake warning light from the reservoir level sensor
Before you order
- Send your VIN — bore size, port count/thread and reservoir style vary by GVWR and year.
- Bench-bleed the master cylinder before installation; skipping it is the number-one reason a replacement “doesn’t fix it.”
- Flush the system with fresh DOT 3/4 fluid; on ABS trucks a scan-tool bleed may be needed if air reaches the modulator.
- If fluid was found in the booster, plan on inspecting or replacing the booster.
Select your truck for a master cylinder quote
Chevrolet
Mitsubishi Fuso
Related parts
Frequently asked questions
Which trucks do you stock a used Master Cylinder for?
Isuzu NPR, NQR and NRR; Ford F-450 and F-550; Chevrolet Silverado and GMC Sierra 4500HD/5500HD plus Kodiak and TopKick C4500; Ram 4500 and 5500; and Mitsubishi Fuso Canter FE125–FE180. Pick your truck below or send us your VIN.
Is a used Master Cylinder tested before it ships?
Yes. Every master cylinder we sell is pulled from a running donor truck, inspected and tested before it ships.
How do I get a quote for a used Master Cylinder?
Use the form on this page or call us. Share your truck and VIN and we confirm exact fitment, then call you back with a price in about 30 seconds during business hours — or email it if we can’t reach you.
Is a used Master Cylinder covered by a warranty?
Yes, we stand behind this master cylinder with our warranty. Exact terms are confirmed on your quote.
Do you ship a used Master Cylinder nationwide?
Yes — we ship to all 48 contiguous states with tracked delivery. Most parts arrive in 3–7 business days; engines, transmissions and axles ship freight and typically arrive in 5–10.
The reservoir is full and nothing leaks — how can it be the master cylinder?
Internal bypass. The piston seals leak inside the bore, so fluid recirculates instead of building pressure — no external evidence at all. A 60-second hold test on the pedal catches it; see our brake-pedal guide.
Is a used master cylinder safe?
A master cylinder from a running donor, pressure-tested before shipping, is functionally the same part your dealer sells — the wear item is the seal set, and wear tracks mileage. We test every hydraulic part and back it with our warranty.
Is the reservoir and cap included?
Yes, as removed from the donor truck.