North Carolina CDL DMV Knowledge Test Class A 1

Gross Vehicle Weight (GVW) is defined as the total weight of a single vehicle in addition to its load.

A header board protects a driver from moving cargo in the event of a crash or emergency stop.

All U.S. states share information about CDL and CLP licenses in a computerized database. If you apply for a license in one state, a state will check this database to verify that you do not already have one such license in another state.

Cargo and its securing devices must be inspected before starting a trip. After beginning a trip, the driver should check the load and securing devices within the first 50 miles on the road, every three hours or 150 miles traveled, and after every break.

To avoid a loss of control, you should accelerate slowly when driving in poor-traction conditions, such as rain or snow.

In extremely hot weather, tire pressure can increase to dangerous levels due to the expansion of the air in heat. To keep an engine from overheating, it is important that there be enough oil and coolant in the engine compartment.

On flatbed trailers and trailers without sides, cargo needs to be tied down. There should be at least one tie-down for every 10 feet of cargo. Regardless of the size of the cargo, at least two tie-downs must be used.

During the on-road driving test, do not stop, change gears, pass another vehicle, or change lanes while any part of your vehicle is in a railroad crossing.

Never apply the brake pedal if your spring breaks are activated. Brakes can be damaged if they are subject to both springs and air pressure.

If you are involved in a crash, the three basic things you need to do are protect the area, notify the proper authorities, and care for anyone injured. It is important to protect the accident site immediately after the accident occurs to help prevent another crash from happening in the same location.

When crossing or entering traffic, bear in mind the size of your vehicle and the distance it will need to accelerate. Wait for a gap in traffic that is large enough to accommodate your vehicle before you begin to accelerate. Remember that you will need more room to accelerate if your vehicle is heavily loaded. Before crossing a road, be sure that you can get all the way across without interfering with traffic.

If your CMV gets stuck on railroad tracks, you should immediately leave the vehicle and get away from the tracks. Check the signposts or signal housing at the crossing for emergency contact information and call 911, or another appropriate emergency number.

Front-end header boards, also known as "headache racks," protect the driver from cargo moving in the event of a crash or emergency stop.

If there is a fire in your vehicle, the first thing you need to do is leave the road and stop. Park in an open area away from anything that could catch fire, such as plants or other vehicles. Do not pull into a service station.

If you are found to have any detectable amount of alcohol in your system while operating a CMV but your blood alcohol concentration (BAC) is still below the legal limit of 0.04 percent, you will be put out-of-service for 24 hours. It is both illegal and dangerous to operate a motor vehicle while under the influence of alcohol.

Distractions that can affect safe driving can be classified as physical (such as reaching for an object), mental (such as talking with passenger), or both (such as talking on a hand-held phone).

When approaching your vehicle, you should check under the vehicle for fresh oil, coolant, grease, or fuel leaks. Spotting any of these before a trip is a cause for concern.

Anti-Lock Braking Systems (ABS) will help you to maintain control during hard braking. ABS will not necessarily shorten your stopping distance.

Do not use the brake pedal when the spring brakes are on. This could damage the brakes by subjecting them to the combined forces of springs and air pressure.

In general, you should always use the parking brake when parking your vehicle. However, you should not apply the parking brake if your brakes are very hot or if your brakes are wet and temperatures are below freezing.

Before inspecting the engine compartment, make sure that the parking brakes are on and/or the wheels are chocked. Check the engine compartment before entering the cab and starting the engine.

When approaching your vehicle before a trip, be sure to look underneath the vehicle for fresh oil, coolant, grease, or fuel leaks.

A low air pressure warning signal is required in vehicles with air brakes. The warning light is usually red and may be accompanied by a buzzer.

Bridges usually freeze before the rest of the road. You should be especially careful when crossing bridges if the temperature is near the freezing point.

In an air brake system, the air storage tanks hold enough air for brakes to be used several times if the compressor stops working.

Before a trip, ensure that the steering box is securely mounted. Check for missing nuts, bolts, and cotter keys. Be sure that there are no power steering fluid leaks and that there is no damage to power steering hoses.

Distracted drivers perceive hazards on the road more slowly than drivers who are focused, or they do not perceive hazards at all.

It is essential that your low pressure warning light function properly. After allowing the system to charge, you can test the warning signal by rapidly applying and releasing the brake pedal. This will release air from the braking system and the warning signal should come on when pressure drops to a dangerous level.

If you remain in neutral for too long while switching gears, you may have difficulty putting the vehicle into the next gear. If this happens, do not try to force the gear shift. Instead, return to neutral, release the clutch, increase the engine speed to match the road speed, and try again.

Eating heavy foods before driving or keeping the temperature in a cab too high can cause a driver to become drowsy while behind the wheel. Exercising and maintaining a healthy diet will help a driver to stay alert while driving.

Blocking is used in the front, in the back, and/or on the sides of a piece of cargo to keep it from sliding while the vehicle is in motion.

A faulty exhaust system is a serious safety hazard. It may allow poisonous fumes to enter the vehicle's cab or sleeper berth.

Even if someone else loads cargo onto a vehicle, the driver is responsible for properly inspecting the cargo, ensuring that it is properly loaded and secured, and ensuring that it does not obscure their view or access to emergency equipment.

Before driving a vehicle with a dual air brake system, you must allow the air compressor time to build up at least 100 psi of air pressure in both the primary and secondary systems.

An air brake system's safety relief valve is located in the tank that is first to receive air from the compressor.