From Wikipedia, the free encyclopedia
Car part
This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Vacuum servo" – news · newspapers · books · scholar · JSTOR (February 2017) (Learn how and when to remove this message) |


A vacuum servo (also called a brake booster, power booster, or power brake unit) is a component used on motor vehicles in their braking system, to provide assistance to the driver by decreasing the braking effort. It uses a vacuum, usually supplied by the engine, to multiply the driver's pedal effort and apply that effort to the master cylinder.[1]
Because the servo depends on the vacuum supplied by a running engine, a check valve is typically used in the vacuum line to maintain residual vacuum without engine support, allowing limited use even after parking.
See also
[edit]Notes
[edit]- ^ "Learn about Hydraulic Brakes - How a vacuum brake servo/booster works". edumech.co.uk. Archived from the original on 2016-04-25. Retrieved 2025-06-25.
External links
[edit]- What is a brake booster? Archived 2023-12-28 at the Wayback Machine
- Nice, Karim. "How Power Brakes Work". HowStuffWorks.com. Retrieved 2025-06-25.
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