NL Air Brake Test 2
- Perfect for first-time and renewal commercial applicants, and those adding endorsements
- Based on 2024 NL commercial driver's licence manual
- Triple-checked for accuracy
- Updated for September 2024
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A commercial truck driver’s licence is required to drive any commercial vehicle in Newfoundland and Labrador. There are two types of driving jobs available: owner-operator and employee. If you plan on running your own business or becoming a driver-for-hire, you will need a truck driver’s licence. To receive a trucking licence, you will have to pass two exams: a commercial knowledge exam with multiple-choice questions and a road test, which will test your general driving skills. To help you study for the knowledge test, we have prepared this second practice exam with 50 questions to test your knowledge of driving large vehicles in Newfoundland and Labrador. We encourage you to read the hints and explanations provided and check out our sources. You will notice that the questions are slightly more difficult. This is because they start to examine some of the more technical definitions and concepts found in the official 2024 NL commercial driver’s manual. Once you have studied these questions, giving another truck driver practice test a try may be a good idea. Good luck!
questions
correct answers to pass
passing score
- If there is a loss of pressure in the trailer supply line, you would expect the trailer brakes to be applied and
- If the air pressure reaches 150 psi, the safety valve will open. Where is the safety valve located?
- The low air warning device must activate by the time that tank air pressure falls to
- Tank air pressure must not drop below _______ while the vehicle is in operation.
- Minimum governor cut-out pressure is
- When you test the system air-loss rate of a bus or straight truck, the maximum acceptable leakage rate is 3 psi within
- Maximum governor cut-out pressure is
- When you test the system air-loss rate, the maximum acceptable leakage rates per minute for a straight truck, a tractor pulling one trailer, and a tractor pulling two trailers are
- With the engine idling at _________, air pressure must rise from 85 to 100 psi within two minutes.
- Minimum governor cut-in pressure is
- The governor cut-in pressure is normally _________ below the cut-out pressure.
- Air pressure must rise _____________ with the engine idling at 600–900 rpm within 2 minutes.
- Before starting the air brake practical test, make sure that air pressure is at least
- The spring brakes will start to apply when the air pressure falls below
- A tractor-trailer with one trailer will fail the air-loss rate test if the loss rate exceeds
- The trailer air supply valve will close automatically if air pressure in the trailer supply line drops to
- A tractor-trailer with two trailers will fail the air-loss rate test if the loss rate exceeds
- Before beginning the air-loss tests of the air braking system, make sure that the air pressure has risen to
- The air-loss rate test can be performed only when
- Air compressors can either be driven by the engine belt and pulleys or
- The spring brake test is passed if the vehicle
- Different sizes of brake chamber on the same axle can cause
- To test the air brakes, the vehicle should be parked
- In a drum brake, the brake linings are attached to
- Where is the air dryer located?
- When draining the air tanks, you observe excessive oil coming out of the supply tank. Which of the following is most likely to be faulty?
- You can usually make a normal stop by applying no more than
- The coil spring in most spring parking brake chambers can exert a force of
- Spring parking brakes typically require air pressures of at least _______ to completely release.
- In the air service circuit, there is a double (two-way) check valve connected to the primary and secondary service tanks. What does this valve do?
- Normally, who can adjust automatic slack adjusters?
- Which statement is true of spring brakes?
- Which colour coding is usually employed for the service line?
- Why are there two service tanks in a modern air brake system?
- What is the most frequent reason for placing a commercial vehicle out of service?
- How can you check whether the trailer spring brakes have activated?
- Which of these vehicles is most likely to be equipped with air brakes?
- Where is the air pressure gauge for the service tanks?
- Which colour is the trailer supply line?
- What can cause the air pressure in the air brake system to drop?
- How do you apply the parking brakes?
- Your vehicle's air compressor is belt driven. How do you check for correct belt tension?
- Which of these is not a part of a drum brake?
- When brakes become overheated, they also become
- What is a "glad hand"?
- To bring a vehicle to a halt in the same distance when its weight has been doubled, the braking force should be what?
- What powers the compressor in a vehicle's air brake system?
- Where does a compressor pump the air in a vehicle's braking system?
- What is leveraged to gain a mechanical advantage in a braking system?
- What causes the wheels to stop spinning in a braking system?