Home › CDL Practice Tests › Air Brakes Questions › Question 179
What is snub braking on a downgrade?
- A.Holding light, steady pressure on the brakes for the entire grade
- B.Pressing the brakes once at the top and never again
- C.Applying the brakes firmly enough to slow the vehicle to about 5 mph below your safe speed, then releasing them and repeating only when speed rises back to that safe speed
- D.Using only the trailer brakes to hold the tractor back
Correct answer
C. Applying the brakes firmly enough to slow the vehicle to about 5 mph below your safe speed, then releasing them and repeating only when speed rises back to that safe speed
Why
Snub braking lets the brakes work in short, effective applications and then cool while they are released. Continuous light dragging keeps heat flowing into the drums with no cooling break, which is how fade is created.
Manual topic: Air Brakes - Downgrade Braking · From the Air Brakes practice bank (AB-179).