CDL Air Brakes TestUsing Air BrakesEasy
A commercial vehicle driver needs to park their air-braked vehicle on a slight upgrade. After stopping and setting the parking brake, what additional safety measure should be taken?
- AChock the wheels only if required by company policy.
- BPump the service brakes to ensure full air release.
- CRelease the parking brake for a few seconds, then reapply it.
- DPlace the vehicle in the lowest gear or reverse.
Show answer & explanationAnswer & explanation
Correct answer: D. Place the vehicle in the lowest gear or reverse.
Placing the vehicle in gear (lowest for upgrade, reverse for downgrade) provides an extra layer of security, using the engine's compression to help hold the vehicle in place, preventing rolling if the parking brake fails.
Why the other options are wrong
- A. Chocking wheels is a crucial safety measure, especially on grades, and should be done regardless of company policy, though it's often a policy requirement.
- B. Pumping the service brakes after setting the parking brake is not a standard or necessary safety measure for parking.
- C. This action serves no safety purpose and could potentially cause the vehicle to roll.
Parking on a Grade (Air Brakes)
When parking an air-braked vehicle on a grade, set the parking brake, and place the transmission in the lowest gear (for upgrades) or reverse (for downgrades) to provide additional security against rolling.
- Use parking brake.
- Use proper gear (low for upgrade, reverse for downgrade).
- Consider chocking wheels.
Memory trick: Parked on a Hill? 'Gear Up, Then Lock It Still!'