SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/cdl-downhill-snub-braking

In the right low gear on a long downgrade, when do you release the brakes?

When you are about 5 mph below your safe speed.

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  1. About 5 mph below your safe speed ✔
  2. About 5 mph above your safe speed
  3. Only at the bottom of the grade

Why: Brake just hard enough to feel a definite slowdown. Release at about 5 mph under your safe speed, then repeat when you are back at the safe speed.

Huh, didn't know that: Each brake application should last about 3 seconds.

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References

Answer: About 5 mph below your safe speed. Brake just hard enough to feel a definite slowdown. Release at about 5 mph under your safe speed, then repeat when you are back at the safe speed.

  1. California Commercial Driver Handbook (DMV) www.dmv.ca.gov/portal/file/california-commercial-driver-handbook-pdf
    When your speed has been reduced to approximately 5 mph below your "safe" speed, release the brakes.
    Checked 2026-10-10.

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