New York General Knowledge CDL Practice Test

This is a free 20-question practice test for the General Knowledge portion of the New York 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 New York State Department 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 New York.

Question 1 of 20

You are driving on a two-lane road. An oncoming driver drifts into your lane. You should:

Steer right onto the shoulder
Flash your high beams
Honk your horn
Brake hard and stop in your lane

Correct. When an oncoming driver drifts into your lane, the safer escape is right onto the shoulder. Steering left risks a head-on if the other driver corrects.

Question 2 of 20

When you double your speed from 20 to 40 mph, the impact in a crash is:

Twice as great
Three times as great
Four times as great
The same

Correct. Crash energy is proportional to the square of speed. Doubling speed quadruples the energy of impact.

Question 3 of 20

What is "black ice"?

Ice that has been salted
A thin layer of ice clear enough that you can see the road through it
Ice on a black-painted road
Ice formed under the truck

Correct. Black ice is a thin, clear sheet of ice that looks like wet pavement. Suspect it whenever the temperature is at or below freezing and the road appears wet.

Question 4 of 20

A "convex mirror" on the side of a tractor:

Provides a wider view, but objects appear smaller and farther away than they really are
Magnifies objects
Has a flat reflection
Cannot be used in daylight

Correct. Convex (curved) mirrors widen the field of view but distort distance perception — objects look smaller and farther than they actually are.

Question 5 of 20

Which of these is a sign of tire failure?

Heavy thumping or vibration
A loud bang
The vehicle pulling to one side
All of the above

Correct. Vibration, a loud bang from a blowout, and pulling to one side are all classic signs of tire failure.

Question 6 of 20

Which of the following is true about driving at night?

Headlights illuminate further than you can stop within
You should drive faster to keep up with traffic
You should drive at a speed that lets you stop within the distance illuminated by your headlights
You can rely on oncoming headlights to help you see

Correct. Drive at a speed where your stopping distance does not exceed the distance you can see — typically 250 feet on low beams, 350-500 feet on high beams.

Question 7 of 20

Which lane is generally the best for a commercial vehicle on a multi-lane highway?

The far left (passing) lane
The middle lane
The right lane (slow lane)
Whichever has the lightest traffic

Correct. The right lane is generally best — it limits lane changes, reduces conflict with merging traffic only on the right, and matches commercial-vehicle speed.

Question 8 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 9 of 20

Which of the following is the best way to prevent a fire in your vehicle?

Carry extra fuel
Smoke only with the windows open
Inspect the vehicle, watch the gauges, and use safe driving practices
Run the engine hot to burn off carbon

Correct. Most fires are preventable through inspection (electrical, fuel-system, tire) and watching gauges, plus prohibiting smoking near fuel and observing safe loading/refueling rules.

Question 10 of 20

Which of these statements about backing a heavy vehicle is true?

Backing is always safe if you go slow
Whenever possible, use a helper outside the vehicle to guide you
Always back from the right side because you can see better
Backing is the same as backing a car

Correct. Backing is always risky for heavy vehicles. Use a helper, communicate with hand signals agreed in advance, back slowly, and if alone, get out and look (G.O.A.L.).

Question 11 of 20

A driver-side skid can cause a tractor-trailer to:

Drift gently
Jackknife
Improve steering
Over-correct only the trailer

Correct. When the drive wheels lose traction and the trailer continues forward, the tractor pivots and the rig jackknifes.

Question 12 of 20

Which is the safest stopping technique for a non-ABS vehicle whose brakes have started to lock up?

Continue braking hard until you stop
Stab braking: brake hard, release, brake hard again
Pump the brakes lightly
Coast in neutral

Correct. On a non-ABS vehicle, stab braking — full brake application until wheels lock, release, repeat — keeps the vehicle straight while still slowing.

Question 13 of 20

You are driving a 60-foot tractor-trailer at 55 mph. The minimum following distance you should maintain is:

4 seconds
5 seconds
6 seconds
7 seconds

Correct. Above 40 mph, add one extra second to the per-10-foot rule. A 60-foot vehicle = 6 seconds + 1 = 7 seconds at 55 mph.

Question 14 of 20

Which of the following is true about the front-end shock absorbers?

They have nothing to do with handling
Worn shock absorbers can cause poor handling and uneven tire wear
They are part of the brake system
They affect only ride comfort, never safety

Correct. Shock absorbers control suspension oscillation. Worn shocks contribute to poor handling, uneven tire wear, and reduced control on rough roads.

Question 15 of 20

Maximum allowable steering-wheel play is approximately:

5 degrees
10 degrees
20 degrees
30 degrees

Correct. Steering wheel play should not exceed 10 degrees (roughly 2 inches on a 20-inch wheel). More than that, the vehicle is hard to steer.

Question 16 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 17 of 20

On a tight curve in a rural mountain road:

Approach at posted speed
Slow down before entering the curve, take a wider line if you can do so safely
Speed up
Stay on the centerline

Correct. Mountain curves often have advisory speeds well below your safe load speed. Slow before entering and use the full lane safely.

Question 18 of 20

You should back from the driver's side rather than the passenger's side when possible because:

You can see better out of the driver's window
It is required by law
Trailers track that direction
Mirrors only work on that side

Correct. Driver-side ("sight side") backing gives the driver direct visual feedback through the open window in addition to mirror checks.

Question 19 of 20

How many red reflective triangles must you carry in your commercial vehicle for emergency warning?

One
Two
Three
Six

Correct. You must carry three red reflective triangles, six fusees, or three liquid-burning flares for emergency warning use.

Question 20 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.

About the New York 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 New York State Department 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 New York CDL practice tests.