Colorado CDL DMV Knowledge Test Class A 1

Gross Vehicle Weight (GVW) is the total weight of a single vehicle and its load of cargo.

In the event of tire failure, hold the steering wheel firmly. Stay off the brakes and let the vehicle slow down on its own. Once the vehicle has slowed considerably, you should brake very gently, pull off the road, and stop.

Before driving during the winter, make sure to check your defrosting and heating equipment, coolant and antifreeze levels, wipers and washers, tire tread, tire chains, lights, reflectors, and exhaust system. Clear ice and snow from all windows, mirrors, hand holds, steps, deck plates, and radiator shutters. Make sure the winterfront is not closed too tightly.

If the low air pressure warning light turns on, you should stop and safely park your vehicle as soon as possible. Controlled braking will be possible only as long as enough air remains in the tanks.

If you must drive in fog, you should use your low beam headlights and fog lights, even during the daytime.

If you encounter a distracted driver, make sure to give them plenty of room. Be very careful if you pass their vehicle because the driver may be unaware of your presence and drift into your lane.

Commercial drivers are required by federal and state laws to inspect their vehicles before every trip. Regular inspections can help drivers identify issues before they become dangerous and costly.

Check each slack adjuster after setting wheel chocks and disengaging the parking brake. Pull the slack adjusters to make sure they do not move more than about one inch from where the push rod is attached. If they move more than one inch, they may be out of adjustment and will need to be fixed.

If you are unsure if a trailer is equipped with an Anti-Lock Braking System (ABS), look under the vehicle for the electronic control unit and wheel speed sensor wires coming from the back of the brakes.

Drivers who are holding conversations with others may not be paying full attention to the road and may make unsafe moves. Children do not always pay attention to traffic and may dart into the road without looking. Exercise caution when driving near road workers. This helps to keep the workers and other distracted drivers safe.

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.

To obtain a hazardous materials endorsement, you will be required to submit your fingerprints and undergo a TSA background check.

To prevent rolling backward when starting from a stop, you should partly engage the clutch before removing your foot from the brake. Apply the parking brake whenever necessary to prevent your vehicle from rolling back.

In an air brake system, pressing and releasing the brake pedal unnecessarily can release air from the braking system faster than the compressor can replace it.

There are two indicators that determine when you need to shift into a higher gear. One indicator is the engine speed (rpm). You should read your vehicle's manual to learn its rpm range and shift up when you reach the top of that range. The other indicator is road speed (mph). You should learn which speeds each gear can accommodate, then keep an eye on the speedometer and shift up as needed.

On a downgrade, the force of gravity will cause a vehicle's speed to increase. When approaching a downgrade, choose to travel at a speed that will be safe for the size and weight of your vehicle.

Some pre-1975 vehicles have a front brake limiting valve, which has "normal" and "slippery" settings. The idea behind these valves was to limit the air pressure available to the front brakes when driving on slippery surfaces, and thereby reduce the danger of a front-wheel skid. Studies have found that this is not actually a concern, so if your vehicle has a front brake limiting valve, leave it in the "normal" position.

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.

In the event of an engine fire, you should turn off the engine as soon as possible. Do not open the hood if you can avoid it. Shoot foam through the louvers or from the vehicle’s underside.

If a tractor is equipped with an Anti-Lock Braking System (ABS) but the trailer is not, the risk of jackknifing will be reduced and the driver should still be able to maintain steering control. If only the trailer is equipped with ABS, it is less likely that the trailer will swing out to one side.

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.

During a pre-trip inspection, belts in the engine compartment should be checked for tightness and excessive wear.

When approaching a curve during the on-road driving skills test, you must reduce your speed sufficiently before entering the curve so that you do not need to further brake or shift in the curve. Keep the vehicle in its lane and continue to check for traffic in all directions.

If a pre-trip inspection reveals anything unsafe about your vehicle, you must get it repaired. It is illegal to operate an unsafe vehicle.

Mirrors should be checked prior to the beginning of a trip. On a vehicle with a trailer, mirror adjustment can only be checked accurately if the connected trailer is straight.

Check your tires regularly when looking in your mirrors. This helps ensure that you will notice a tire fire, if one should happen. Tire fires may occur when a tire is under-inflated, if dual tires are touching, or if the tires are otherwise overheated.

Being under stress can lead to aggressive driving, which is dangerous. Playing calming music can help you become more relaxed if you are feeling stressed while driving.

Before adding coolant to a system without a recovery or overflow tank, you must turn the engine off and wait until it cools. Use gloves or a thick cloth to protect your hands. To release the pressure seal, turn the radiator cap slowly to the first stop.

ABS is equipped in addition to a vehicle's normal braking system and it neither increases nor decreases the vehicle's braking capability. ABS activates during hard applications of the brake pedal in order to prevent wheels from locking up.

A high center of gravity makes a vehicle more likely to tip over.

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.

Driving drowsy is dangerous and should always be avoided. Warning signs of drowsiness include frequent blinking, your eyes closing or going out of focus by themselves, frequent yawning, and drifting between lanes.

A modulating control valve allows a driver to gradually apply spring brakes. In equipped vehicles, the valve is controlled by a lever located on the dashboard.

Skids caused by acceleration can usually be corrected by taking your foot off of the accelerator. If you are on an especially slippery surface, you may also need to push the clutch in.

A tire load rating is the maximum safe weight that can be carried by a tire at a specified pressure. This number is stated on the side of each tire.