District Of Columbia CDL DMV Knowledge Test Class B 2

Missing clamps, spacers, studs, or lugs can be a dangerous defect. Mismatched, bent, or cracked lock rings are not safe to be used. Wheels or rims with welded repairs are not safe.

Many large vehicles have curved, convex mirrors. Convex mirrors allow drivers to see a wider area than flat mirrors. However, they also make objects seem smaller and farther away than they really are.

In a vehicle with dual parking control valves, there is a separate air tank that can be used to temporarily release the spring brakes if they have been activated due to low air pressure. Pushing in the proper control will release the spring brakes for a short period of time, allowing the driver to move the vehicle in an emergency.

You should finish each exercise with your vehicle in the exact position described by the examiner. You can be penalized for failing to complete an exercise exactly in the manner described by the examiner, potentially resulting in failure of the basic control skills test.

Cargo must be properly secured to prevent it from moving in transit. Loose cargo can be dangerous to the driver operating the CMV, as well as to other road users.

Stimulant drugs, including caffeine, are not helpful as a way of avoiding fatigue. They may help keep you awake, but will not make you any more alert. Feeling tired is a sign that your body needs sleep, and the only way to properly address it is to stop driving and get some sleep.

Most heavy vehicles with manual transmissions require double clutching to change gears. A driver should release the accelerator, push in the clutch, and shift into neutral at the same time. After releasing the clutch and allowing the vehicle to change to the necessary speed, the driver should push in the clutch, shift gears, then simultaneously release the clutch and accelerate.

After an accident, spilled fuel and improper use of flares can result in a fire.

When turning quickly to avoid colliding with a hazard in the roadway, you should always keep both hands on the steering wheel. You must have a firm grip on the wheel to be able to turn quickly.

Compressed air in an air brake system usually contains a certain amount of water and compressor oil. The water and oil can damage the brakes if left to accumulate in the system. Tanks must be drained regularly to remove this build-up.

When transporting cargo on a flatbed trailer, you should use at least one tie-down for every 10 feet of cargo. Any cargo, no matter how small, should be restrained by a minimum of two tie-downs.

A wig wag is a type of low air pressure warning device in an air brake system. It drops a mechanical arm into the driver's view when the air pressure in the tanks falls below 60 psi.

Drivers with blocked vision may pose hazards to others on the road. Examples of such drivers include those who haven't scraped ice off of their windshields; those driving vehicles loaded with large items blocking the windows; and those who are driving rental trucks without being used to the limited rear visibility of a truck.

As a part of earning your CDL, you will have to pass an inspection test and demonstrate that your vehicle is safe for operation. During the vehicle inspection test, you will have to walk around the vehicle and point to or touch each item and explain to the examiner what you are checking and why. You will not have to crawl under the hood or under the vehicle.

Because live animals can lean during curves, and otherwise move in transit, the weight distribution of a cargo of livestock is unstable. Driving with livestock requires special care.

When inspecting the engine compartment, you should check the oil level, coolant level, and windshield washer fluid level, among other things.

Traffic violations classified as "serious" include excessive speeding, reckless driving, operating a CMV without a valid CDL, following other vehicles too closely, and improper lane usage. Consequences for multiple serious traffic violations can result in license disqualification.

During the on-road driving skills test, you may be asked to drive on an expressway. Make sure you maintain proper lane positioning, vehicle spacing, and vehicle speed. Continue to thoroughly check traffic in all directions while on the expressway.

Cargo should be inspected by a driver to ensure that it is properly secured, balanced, and not exceeding weight limits.

Factors that can affect your vehicle's stopping distance include driving speed, the vehicle's weight, and the slipperiness of the road surface.

Water and compressor oil are removed from air storage tanks through a drain valve. The water and oil can damage the brakes if left to accumulate in the system. Manually operated tanks must be drained every day to remove this build-up.

Cargo needs to be secured appropriately to prevent it from moving in transit. Cargo should be arranged to keep the vehicle's center of gravity low and well-distributed.

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.

When exiting your vehicle during the basic vehicle control skills test, you must face the vehicle and maintain three points of contact at all times. If your testing vehicle is a bus, you must maintain contact with the handrail. Exiting the vehicle incorrectly may result in automatic failure of the basic control skills test.

On flatbed trailers or trailers without sides, cargo must be tied down to keep it from shifting or falling off in transit.

An engine can be rapidly destroyed if it is run without oil. If its oil pressure gauge is low or fluctuating, do not operate a vehicle.

Remaining in neutral for too long when shifting gears may make it difficult to put the vehicle into the next gear.

When inspecting an exhaust system, you should verify that parts of the system are not loose, broken, or missing. The system's parts must be properly mounted and should not be rubbing against moving parts of the vehicle.

During the basic vehicle control skills test, a pull-up will be scored any time an applicant stops and pulls forward to gain a better position. Stopping without changing direction will not. An excessive number of pull-ups will count as errors.

If you are turning to avoid a hazard, do not apply the brakes while you are turning. This could easily lock the wheels and create a skid.

Driving while fatigued is dangerous. Warning signs of fatigue include difficulty focusing; repeated yawning or rubbing of the eyes; daydreaming or wandering thoughts; and drifting out of your lane.

To avoid being blinded by the lights of oncoming vehicles, you can glance to the right side of the road until the vehicle has passed.

Driving at excessive speeds is a major cause of fatal crashes. Never drive above the posted maximum speed limit and adjust your speed to fit conditions.

Because air pressure can eventually leak away, the emergency brakes in an air brake system must be held on by mechanical force.

Backing a large CMV is always dangerous because you will not be able to see everything behind you. If you must back up, use a helper, if possible.