CDL Tank Vehicles (N) Endorsement Test
Liquid surge: practice questions
Our CDL Tank Vehicles bank has 15 questions on this topic. Here are 5 of them with answers; the full mock exam draws from every topic, like the real one.
Question 1
To control surge, when should you start braking for a stop?
- Only once the surge has started
- Far in advance of the stop
- When the vehicle ahead brakes hard
- At the last possible moment
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B. Far in advance of the stop — Brake far in advance of a stop and increase your following distance (CDL Manual 8.3.2)
Question 2
What does the manual say a liquid tanker driver must be very familiar with?
- The tank's paint scheme
- The shipper's billing system
- The route's toll prices
- How the vehicle handles
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D. How the vehicle handles — The driver of a liquid tanker must be very familiar with the handling of the vehicle (CDL Manual 8.2.2)
Question 3
Which federal knowledge topic deals directly with surge?
- Coupling and uncoupling triple trailers
- Causes, prevention and effects of cargo surge on handling
- Proper use of the stop signal arm
- Passenger loading and unloading
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B. Causes, prevention and effects of cargo surge on handling — 49 CFR 383.119(a): causes, prevention and effects of cargo surge on motor vehicle handling
Question 4
What is controlled braking?
- Braking as hard as you can without locking the wheels, with small steering moves
- Using only the engine brake to slow down
- Braking with the trailer hand valve only
- Pressing the pedal to the floor and holding it
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A. Braking as hard as you can without locking the wheels, with small steering moves — Controlled braking: apply the brakes as hard as you can without locking the wheels, and keep steering wheel movements very small (CDL Manual 2.17.2)
Question 5
When the surge wave hits the end of the tank, what does it do to the truck?
- Has no effect on a stopped truck
- Pushes it in the direction the wave is moving
- Lifts the front wheels off the road for a moment
- Pulls it backward toward the wave
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B. Pushes it in the direction the wave is moving — When the wave hits the end of the tank, it tends to push the truck in the direction the wave is moving (CDL Manual 8.2.2)