SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/cdl-no-pedal-with-spring-brakes

Why should you never push the brake pedal down when the spring brakes are on?

The combined force of springs and air can damage the brakes.

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  1. It drains the air tanks completely
  2. Spring and air force together can damage the brakes ✔
  3. It turns off the ABS

Why: With the spring brakes on, adding air pressure from the pedal doubles the force on the brakes. Some systems prevent this, but not all, so make it a habit.

Huh, didn't know that: Many brake systems are designed so this will not happen, but they may not always work.

The dad joke
Why did the brake pedal take a day off? It was feeling a little pushed around.
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References

Answer: Spring and air force together can damage the brakes. With the spring brakes on, adding air pressure from the pedal doubles the force on the brakes. Some systems prevent this, but not all, so make it a habit.

  1. California Commercial Driver Handbook (DMV) www.dmv.ca.gov/portal/file/california-commercial-driver-handbook-pdf
    the brakes could be damaged by the combined forces of the springs and the air pressure.
    Checked 2026-10-10.

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