In Partnership with Exeter Public Library

View instructions
The air brakes endorsement applies to applicants who wish to drive a vehicle with air brakes in Class A, B, or C CDL. To drive a vehicle with air brakes, you must pass the air brake component of the New Hampshire CDL knowledge test. The NH CDL air brakes test consists of 25 questions, and you'll need at least 20 correct answers to pass (80%). The test covers the information found in the air brakes section of the New Hampshire CDL Manual. Take this NH CDL practice test now to prepare for the actual air brakes test!
1. Some air brake systems have an alcohol evaporator to:
reduce the danger of slipping.
force the brake shoes away from one another.
reduce the stopping power of the vehicle.
prevent ice from forming in the brake system.
2. When driving in very hot weather, the heat will increase the chances of:
suspension system defects.
tire failure.
ABS malfunction.
loss of hydraulic pressure.
3. You hear a loud "bang" which sounds like a tire blowout. You should:
check the tires at the next stop.
keep driving as normal.
inspect your tires with your mirrors.
assume you have a tire failure.
4. To make the brakes work, air brakes use:
nitrogen.
compressed air.
hydraulic air.
carbon monoxide.
5. The alcohol evaporator:
shows how much air pressure you are applying to the brakes.
helps to reduce the risk of ice in air brake valves and other parts in cold weather.
ensures the coolant temperature gauge remains in the normal range.
eliminates the need for daily air tank drainage.
6. Before driving a vehicle with a dual air brake system, you should allow time for the air compressor to build up a minimum of ____ pressure in both the primary and secondary systems.
150 psi
35 psi
50 psi
100 psi
7. Rough acceleration:
is recommended during long trips.
improves gas mileage.
is necessary to warm up the engine.
can cause mechanical damage.
8. One way to prevent hydroplaning is to:
make sure you have enough tread on your tires.
have less than 4/32 inch tread depth in every major groove on front tires.
take curves at higher speeds.
use the controlled braking method.
9. At passive railroad crossings, even if there are active railroad signals that indicate the tracks are clear, you must _________  to be sure it is safe to proceed.
listen, look and stop
go, stop and listen
go, look and put the transmission in neutral
stop, look, and listen
10. Why must air tanks be drained?
The low boiling point of water reduces braking power.
To keep from fouling the air compressor oil.
Water and oil reduce the air pressure.
Water can freeze in cold weather and cause brake failure.
 
Page 1 of 3
Next page

NH CDL Air Brakes Test

Number of questions: 25
Correct answers to pass:20
Passing score:80%
Share This Online CDL Test
Rate this CDL Air Brakes Test
4.8 out of 5
based on 408 votes