300+ Free NH CDL General Knowledge Practice Questions

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Key Facts: NH CDL General Knowledge Exam

New Hampshire General Knowledge questions

NH DMV Saf-C 1805

80%

Minimum CDL knowledge-test passing score

NH DMV / FMCSA

Minimum age for New Hampshire CDL or CLP

NH DMV CDL Manual

Minimum age for interstate operation or hazardous materials

NH DMV CDL Manual

$20

Commercial Learner Permit fee

NH DMV DSMV 312

$60

Class A, B, or C CDL fee

NH DMV DSMV 312

New Hampshire CDL applicants must pass the 50-question General Knowledge exam with at least 80 percent before receiving a CLP. NH DMV states applicants must be at least 18 for a CDL or CLP and at least 21 to drive interstate or haul hazardous materials. After passing the required knowledge exams, applicants receive a 180-day CLP and must wait at least 14 days before attempting the skills examination. The NH CDL application lists a $20 CLP fee and a $60 CDL Class A, B, or C fee.

Sample NH CDL General Knowledge Practice Questions

Try these sample questions to test your NH CDL General Knowledge exam readiness. Each question includes a detailed explanation. Start the interactive quiz above for the full 300+ question experience with AI tutoring.

1When performing a pre-trip inspection, the driver should ensure that the steering wheel free play (lash) does not exceed what limit?

A.5 degrees in either direction

B.10 degrees in either direction (approximately 2 inches on a 20-inch wheel)

C.15 degrees in either direction

D.20 degrees in either direction

Explanation: Federal Motor Carrier Safety Regulations require that steering wheel free play (lash) not exceed 10 degrees in either direction, which translates to roughly 2 inches of movement on a 20-inch diameter steering wheel before the front wheels begin to turn. Excessive free play indicates worn steering components and can make precise steering difficult, especially in emergency maneuvers. A vehicle with excessive steering lash would be placed out of service.

2During the cab check portion of a pre-trip inspection, you should test the parking brake by:

A.Driving forward slowly and applying the parking brake

B.Putting the vehicle in gear with the parking brake set and gently pressing the accelerator to see if the vehicle holds

C.Visually checking that the parking brake handle is in the correct position

D.Checking the parking brake cable under the vehicle

Explanation: To properly test the parking brake, set the parking brake, put the vehicle in a low gear, and gently press the accelerator to see if the brake holds the vehicle in place. This functional test confirms the parking brake can actually prevent the vehicle from moving, which is essential for safety when parked on grades. A visual check alone is insufficient because it does not verify that the brake mechanism is actually functioning properly.

3Which emergency equipment is required to be on a commercial motor vehicle?

A.Fire extinguisher, spare fuses, and three red reflective triangles

B.First aid kit, fire extinguisher, and flares only

C.Fire extinguisher and road flares only

D.Spare tire, jack, and reflective vest

Explanation: Federal regulations require every commercial motor vehicle to carry a properly charged and rated fire extinguisher (minimum 5 B:C rating, or two 4 B:C extinguishers), spare electrical fuses (unless the vehicle has circuit breakers), and three red reflective warning triangles (or equivalent). These items are checked during inspections and roadside enforcement stops. A vehicle missing any of these required items can be cited for a violation.

4A post-trip inspection report is important because:

A.It is only required for vehicles carrying hazardous materials

B.It alerts the carrier to vehicle defects that may need repair before the vehicle is driven again

C.It replaces the need for the next driver to do a pre-trip inspection

D.It is optional but recommended by the FMCSA

Explanation: The post-trip inspection report (also called a DVIR, or Driver Vehicle Inspection Report) is required by FMCSA regulations (49 CFR 396.11). Its purpose is to document any defects or deficiencies discovered at the end of the trip so the carrier can arrange repairs before the vehicle is dispatched again. The next driver must review the previous post-trip report and verify that any noted defects have been repaired or certified as not needing repair. It does not replace the next driver's pre-trip inspection obligation.

5Which of the following is an out-of-service condition that would prevent a vehicle from being driven?

A.A small crack in the windshield that does not obstruct the driver's view

B.A missing mud flap on a rear wheel

C.Brake lining thickness below the minimum allowed by regulations

D.A broken antenna on the CB radio

Explanation: Brake lining worn below the minimum thickness specified in FMCSA out-of-service criteria is a critical safety defect. The North American Standard Out-of-Service Criteria lists specific thresholds: brake lining must not be less than 1/4 inch thick at the thinnest point for air-braked vehicles. When brake linings are too thin, braking effectiveness is severely compromised, and the vehicle must be placed out of service until repairs are made. A small windshield crack not in the driver's view, a missing mud flap, or a broken CB antenna are defects but not typically out-of-service conditions.

6During the pre-trip inspection, which of the following should a driver check regarding the exhaust system?

A.Only that the muffler is present

B.That the exhaust system is secure, not leaking, and not in contact with fuel lines, wiring, or air lines

C.Only that exhaust fumes are not entering the cab

D.That the catalytic converter is functioning properly by checking emissions color

Explanation: When inspecting the exhaust system, the driver should verify that all components are properly mounted and secured, there are no leaks (which could allow poisonous carbon monoxide to enter the cab), and the exhaust system is not in contact with fuel supply lines, wiring, or air brake lines. Heat from the exhaust can damage these components, potentially causing fuel leaks, electrical fires, or brake failures. A complete exhaust system inspection goes beyond just checking for the presence of a muffler.

7What is the minimum tread depth required for steer axle tires on a commercial motor vehicle?

A.2/32 of an inch

B.4/32 of an inch

C.6/32 of an inch

D.1/32 of an inch

Explanation: Federal regulations require steer axle tires to have a minimum tread depth of 4/32 of an inch (approximately 3.2 mm) in every major groove. Steer tires have a higher minimum than other axle positions (which require only 2/32 of an inch) because the steer tires are critical for directional control of the vehicle. Tires below this minimum are considered unsafe and will result in a violation or out-of-service order during an inspection.

8What is the minimum tread depth required for tires on drive and trailer axle positions?

A.4/32 of an inch

B.2/32 of an inch

C.6/32 of an inch

D.1/32 of an inch

Explanation: Tires on drive axles and trailer axles must have a minimum tread depth of 2/32 of an inch in every major tread groove. This is less than the 4/32-inch requirement for steer axle tires because drive and trailer tires, while important for traction and braking, are not as critical for directional control as steer tires. However, insufficient tread on any axle reduces traction, increases stopping distance, and raises the risk of hydroplaning on wet roads.

9When inspecting slack adjusters on an S-cam brake system, the pushrod stroke at the brake chamber should not exceed what general limit?

A.1/2 inch

B.1 inch

C.The adjustment limit varies by chamber size, but generally should not exceed about 2 inches

D.4 inches

Explanation: The maximum allowable pushrod stroke depends on the specific brake chamber size (type 16, 20, 24, 30, etc.), but as a general rule, pushrod travel should not exceed approximately 2 inches for most common chamber sizes. When pushrod travel is excessive, the brakes are out of adjustment and will not provide adequate stopping power. Specifically, a type 30 long-stroke chamber has a maximum of 2.5 inches. Checking slack adjuster stroke is a critical part of the brake inspection because out-of-adjustment brakes are one of the most common out-of-service violations found during roadside inspections.

10During a tire inspection, you notice a bulge on the sidewall of one of the steer tires. What should you do?

A.Continue driving but avoid high speeds

B.Have the tire replaced before driving the vehicle

C.Rotate the tire to a non-steer position

D.Reduce air pressure to alleviate the bulge

Explanation: A sidewall bulge indicates internal structural damage to the tire, meaning the reinforcing plies inside the tire have broken. This is extremely dangerous because the tire can blow out without warning. The tire must be replaced before the vehicle is driven. This is especially critical on steer tires, where a blowout can cause the driver to lose directional control. Reducing air pressure will not fix the problem, and rotating the tire to another position still leaves a dangerously damaged tire on the vehicle.

About the NH CDL General Knowledge Exam

The New Hampshire CDL General Knowledge test is the base knowledge examination for New Hampshire CDL applicants. NH rules identify it as a 50-question multiple-choice test for all applicants, with an 80 percent passing grade. The exam is grounded in the New Hampshire Commercial Driver License Manual and federal CDL minimum standards, covering safe operation regulations, vehicle inspection, basic vehicle control, shifting, backing, visual search, communication, speed and space management, adverse conditions, hazards, emergencies, skid recovery, cargo control, driver wellness, alcohol and drug effects, and New Hampshire CDL licensing requirements.

Assessment

New Hampshire rules list a 50-question multiple-choice General Knowledge test for all CDL applicants; FMCSA requires basic CDL knowledge tests to meet federal knowledge and passing-score standards.

Time Limit

Knowledge examinations are available from 8:00 a.m. to 3:00 p.m. at current NH DMV locations; no separate official time limit found

Passing Score

80% minimum on each CDL knowledge examination

Exam Fee

$20 Commercial Learner Permit; $60 CDL Class A, B, or C license; $10 most endorsements; $30 hazardous materials endorsement (New Hampshire Division of Motor Vehicles (NH DMV))

NH CDL General Knowledge Exam Content Outline

NH CDL Manual Forward; Saf-C 1805

New Hampshire CDL Basics

CDL/CLP eligibility, application form DSMV 312, medical-card filing, 50-question General Knowledge exam, 80% passing grade, 180-day CLP, 14-day skills-test wait, and fees

49 CFR 383.111(a)(17)

Vehicle Inspection

Pre-trip, enroute, and post-trip inspections; brakes, tires, lights, steering, suspension, leaks, mirrors, and defect reporting

49 CFR 383.111(a)(4)-(6)

Basic Control, Shifting, and Backing

Starting, stopping, backing, turning, off-tracking, shifting procedures, speed control, and maneuvering large vehicles

49 CFR 383.111(a)(7)-(10)

Seeing, Communication, Speed, and Space

Visual search, mirror use, signaling, communicating presence, stopping distance, following distance, traffic gaps, and overhead clearance

49 CFR 383.111(a)(11)-(15), (19)-(20)

Adverse Conditions and Emergencies

Night driving, fog, rain, heat, mountain grades, hazard perception, evasive steering, brake failure, blowouts, fires, skids, and fatigue

49 CFR 383.111(a)(1), (16), (18)

Cargo, Alcohol, Drugs, and Regulations

Cargo securement, weight distribution, driver responsibilities, general hazmat awareness, fatigue, health, and alcohol/drug effects

How to Pass the NH CDL General Knowledge Exam

What You Need to Know

Passing score: 80% minimum on each CDL knowledge examination
Assessment: New Hampshire rules list a 50-question multiple-choice General Knowledge test for all CDL applicants; FMCSA requires basic CDL knowledge tests to meet federal knowledge and passing-score standards.
Time limit: Knowledge examinations are available from 8:00 a.m. to 3:00 p.m. at current NH DMV locations; no separate official time limit found
Exam fee: $20 Commercial Learner Permit; $60 CDL Class A, B, or C license; $10 most endorsements; $30 hazardous materials endorsement

Keys to Passing

Complete 500+ practice questions
Score 80%+ consistently before scheduling
Focus on highest-weighted sections
Use our AI tutor for tough concepts

NH CDL General Knowledge Study Tips from Top Performers

1Read the New Hampshire CDL manual introduction and Sections 1, 2, and 3 first; those sections anchor the General Knowledge exam for CDL classes.

2Memorize New Hampshire logistics: 50 General Knowledge questions, 80% passing grade, $20 CLP, $60 CDL class fee, 180-day CLP, and 14-day wait before skills testing.

3Use 49 CFR 383.111(a) as a checklist: inspection, basic control, shifting, backing, seeing, communication, speed, space, night, weather, hazards, emergencies, skids, cargo, mountain driving, and fatigue all matter.

4Practice inspection questions by naming the defect, the risk, and whether the vehicle should be driven before repair.

5For speed and space questions, think stopping distance first: large vehicles need more room, and poor traction or visibility requires slower speeds and larger gaps.

6Do not over-study endorsement-only topics before General Knowledge unless they overlap with the general scope, such as basic hazardous-materials awareness or air-brake inspection concepts for your vehicle.

Frequently Asked Questions

Who must take the New Hampshire CDL General Knowledge test?

New Hampshire rules list the General Knowledge test as a 50-question multiple-choice examination for all CDL applicants. Applicants may also need additional knowledge tests for air brakes, combination vehicles, endorsements, or other vehicle types.

What score do I need to pass the New Hampshire CDL General Knowledge test?

New Hampshire requires an 80 percent passing grade for each CDL knowledge examination. FMCSA also requires at least 80 percent correct on CDL knowledge tests.

How many questions are on the New Hampshire CDL General Knowledge test?

New Hampshire Saf-C 1805.01 lists the General Knowledge examination as 50 multiple-choice questions for all applicants.

How much does the New Hampshire CDL process cost?

The NH DMV CDL application lists a $20 Commercial Learner Permit fee, $60 for Class A, B, or C CDL, $10 for most endorsements, and $30 for a hazardous materials endorsement.

Can I get a New Hampshire CDL if I am under 21?

Yes. The New Hampshire CDL manual states applicants must be at least 18 to get a CDL or CLP, but must be at least 21 to drive interstate or haul hazardous materials.

How long is a New Hampshire CLP valid before the skills test?

The New Hampshire CDL manual states that successful knowledge-test applicants receive a 180-day CLP and must wait at least 14 days after receiving the CLP before attempting the skills examination.

300+ Free NH CDL General Knowledge Practice Questions

New Hampshire CDL General Knowledge Test

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