Alaska General Knowledge CDL Practice Test

This is a free 20-question practice test for the General Knowledge portion of the Alaska Commercial Driver's License knowledge exam. Questions are pulled from a pool of 97 drawn from the AAMVA CDL Manual, which is the source document the Alaska Division of Motor Vehicles uses to write its actual exam.

How it works: Click an answer. The correct choice highlights in green, and you'll see a short explanation. Aim for 85% or better before you sit for the real test in Alaska.

Question 1 of 20

When approaching a railroad crossing, drivers of buses, school buses, and placarded hazmat vehicles must:

Speed up to clear quickly
Stop between 15 and 50 feet from the nearest rail and listen
Cross only if a train is in sight
Sound the horn

Correct. Buses, school buses, and placarded hazmat vehicles must stop at every crossing, 15 to 50 feet from the nearest rail. Look and listen, then proceed when safe.

Question 2 of 20

Which is the proper position for your hands on the steering wheel?

Both hands on the same side
One hand on top, one in your lap
Both hands firmly on opposite sides of the wheel (e.g., 9 and 3)
One hand on the wheel, one on the gear shift

Correct. Both hands should be on opposite sides of the wheel — typically the 9 o'clock and 3 o'clock positions — for steering control.

Question 3 of 20

When should you place reflective triangles on a divided highway after stopping due to a breakdown?

10, 50, and 100 feet behind the vehicle
10 feet to the rear, 100 feet to the rear, and 200 feet to the rear
10, 100, and 200 feet to the rear, on the traffic side
100, 200, and 500 feet to the rear

Correct. On a divided highway with traffic from one direction, place triangles 10, 100, and 200 feet behind the vehicle, on the shoulder or in the lane you stopped in.

Question 4 of 20

Which of these is a major cause of crashes in heavy vehicles?

Driver fatigue
Heavy traffic
Following too closely
All of the above

Correct. Fatigue, heavy traffic, and following too closely are all leading factors in commercial vehicle crashes.

Question 5 of 20

Hazardous materials awareness is required for:

Only Hazmat-endorsed drivers
Every CDL holder, even without an H endorsement
Only owners
Only mechanics

Correct. Every CDL applicant must understand basic hazmat awareness — recognizing placards, labels, and shipping papers — even if they never haul hazmat.

Question 6 of 20

How often must drivers inspect their cargo and securing devices?

Within the first 50 miles, then every 150 miles or every 3 hours of driving (whichever comes first)
Only at the start of the trip
Only at fuel stops
Only when entering a new state

Correct. Federal rule: inspect within the first 50 miles, then every 150 miles or 3 hours of driving, whichever comes first, plus every change of duty status.

Question 7 of 20

A driver who notices their vehicle is overweight should:

Continue and hope for the best
Stop, off-load excess weight, or have the load adjusted before continuing
Drive only at night
Drive faster

Correct. Overweight vehicles violate axle and gross-weight limits, damage roads, increase stopping distance, and incur fines. Adjust the load before continuing.

Question 8 of 20

When the brake pedal feels spongy on an air-brake vehicle:

It is normal
Stop and have the system checked — there may be air in the system or another issue
Drive faster
Pump the brakes harder

Correct. A spongy or unusual feel in air-brake pedals indicates a system issue. Have it inspected before continuing.

Question 9 of 20

On a 6-tire single vehicle, the maximum allowable air loss rate (engine off, brakes released) is:

1 psi per minute
2 psi per minute
3 psi per minute
4 psi per minute

Correct. For a single vehicle, no more than 2 psi per minute leakage with the engine off and brakes released. Combinations are limited to 3 psi/min.

Question 10 of 20

You are driving a 40-foot vehicle at 35 mph. The minimum following distance you should maintain is:

2 seconds
3 seconds
4 seconds
7 seconds

Correct. The rule of thumb: 1 second per 10 feet of vehicle length below 40 mph. A 40-foot vehicle therefore needs 4 seconds of following distance.

Question 11 of 20

Which type of fire extinguisher should you use on an electrical fire?

Class A
Class B
Class C
Class D

Correct. Class B:C dry-chemical extinguishers (often labeled "B:C" or "ABC") are appropriate for electrical fires. Never use water on an electrical fire.

Question 12 of 20

When stopping at the scene of an accident, you should:

Move your vehicle into traffic to make room
Park well off the road, set out warning devices, and offer assistance
Leave the scene immediately
Drive around the accident

Correct. Park clear of the road, activate four-way flashers, set out warning triangles, and assist as you can without putting yourself in danger.

Question 13 of 20

Aggressive driving includes:

Tailgating, weaving, and excessive speed
Driving the speed limit
Yielding the right of way
Using turn signals

Correct. Aggressive driving covers tailgating, lane weaving, excessive speed, running red lights, and other reckless behaviors. Avoid both committing and reacting to it.

Question 14 of 20

You are driving on a wet road. To test how slippery the road is, you can:

Brake hard at 50 mph
Accelerate hard and listen for tire spin
Gently apply the brakes at low speed
Look at other vehicles' tires

Correct. At low speed and in a safe place, you can gently test traction by lightly applying the brakes or by gently accelerating. Hard braking at high speed is dangerous.

Question 15 of 20

Stopping distance increases significantly when:

Brakes are wet
Tires are worn
You are heavily loaded
All of the above

Correct. Wet brakes, worn tires, heavy load, and slick pavement all extend stopping distance. Plan ahead and follow at greater intervals.

Question 16 of 20

A safe practice when entering a freeway is to:

Stop at the end of the on-ramp and wait
Use the entire on-ramp to accelerate to traffic speed and merge into a gap
Slow to 25 mph regardless of traffic
Force traffic to make space

Correct. Use the on-ramp to match traffic speed before merging. Stopping at the end of an on-ramp is dangerous.

Question 17 of 20

On a vehicle equipped with ABS, you should:

Pump the brakes during emergency stops
Apply the brakes the way you always have, with steady pressure
Use the parking brake instead
Never use the service brakes

Correct. With ABS, brake the way you always would. The system prevents wheel lockup automatically; pumping interrupts ABS function.

Question 18 of 20

You are driving on a steep downgrade and your brakes have failed. The best escape is to:

Pump the brakes furiously
Use a runaway escape ramp
Try to bail out of the cab
Sound the horn and continue

Correct. If a runaway escape ramp is available, use it. Modern arrester beds use loose gravel or sand to slow the vehicle without injury to the driver.

Question 19 of 20

You should signal:

Only when other vehicles are visible
Continuously while driving
Well before any turn or lane change, and signal long enough to communicate
Only when changing lanes left

Correct. Signal early, signal long enough that other drivers see and process the signal, and cancel after the maneuver.

Question 20 of 20

Which of the following is a cab in-vehicle inspection item?

Steering wheel free play
Headlights
Tire condition
Lug nuts

Correct. Steering-wheel free play is checked from the driver seat and should not exceed 10 degrees (about 2 inches on a 20-inch wheel).

About the Alaska General Knowledge exam

Most state DMVs administer 50 General Knowledge questions and require 80% (40 correct) to pass. Questions are pulled from a much larger pool, so two applicants taking the test on the same day will see different mixes. The questions on this site are drawn from the AAMVA CDL Manual chapters that every state's exam is built from.

The Alaska Division of Motor Vehicles follows the federal CDL standards established by FMCSA. To earn the General Knowledge credential, you must answer at least 80% of the questions correctly. Many candidates score lower the first time because the test pulls from a large pool — refreshing this page will give you a different mix of questions, drawn from the same authoritative source.

Want more practice? Try the full General Knowledge question bank or browse all Alaska CDL practice tests.