CDL General Knowledge

With an engine fire, you should do all of the following EXCEPT? A. Turn off the engine as soon as you can B. Open the hood to allow air in C. Shoot foam through the louvers, radiator or the vehicle's underside D. Pull off the road as soon as possible

Open the hood to allow air in. With an engine fire, you should avoid opening the hood if possible, because allowing more air to the fire can cause it to burn more and spread.

If your brakes fail, which of the following is NOT a useful method to slow your vehicle? A. Pump the brakes B. Put the vehicle in a higher gear C. Use the parking brake D. Use an escape ramp

Put the vehicle in a higher gear. This is incorrect because putting the vehicle in a higher gear will cause it to go faster - you should downshift to slow the vehicle down. Pumping the brakes may help generate enough hydraulic pressure to stop the vehicle. Using the parking brake, or using an escape ramp are also effective methods to slow your vehicle down if your brakes fail.

Engine braking is most effective when: A. RPMs are low and transmission gear is high B. RPMs are high and transmission gear is low C. RPMs are low and transmission gear is low D. RPMs are high and transmission gear is high

RPMs are high and transmission gear is low. The greatest effect of engine braking occurs when the RPMs are high (near the governed RPM limit) and the transmission is in a lower gear.

1. What is the most important reason for doing a vehicle inspection?

Safety is the most important reason you inspect your vehicle, safety for yourself and for other road users

Which of the following would NOT be part of a standard vehicle inspection? A. Tire problems B. Bad brake drums or shoes C. Steering system defects D. Seating defects

Seating defects. A standard vehicle inspection should check for tire problems, brake problems, steering problems, as well as: wheel and rim problems, suspension system defects, exhaust system defects, emergency equipment and cargo (for trucks)

The cumulative effect of not getting enough sleep is known as ____? A. Sleep debt B. Insomnia C. Sleep apnea D. Micro-sleep

Sleep debt. Sleep debt occurs when you don't get enough sleep and you "owe" your body more sleep. The only way to "pay off" your sleep debt is to get more sleep. Insomnia (inability to initiate or maintain sleep) or Sleep apnea (pauses in breathing while asleep) are potential causes of sleep debt. Micro-sleep are brief naps that last for 4 or 5 seconds that may occur if you are too drowsy to drive.

Which of the following is NOT a part of the steering system? A. Main spring B. Hydraulic fluid reservoir C. Tie rod D. Steering knuckle

The main spring is part of the suspension system. The rest of the answers are part of the steering system.

Which of the following statements about alcohol is TRUE? A. Drinking black coffee and taking a cold shower will help sober you up. B. Most people can drink 2 beers without affecting their driving skills C. Time is the only method that works to sober you up D. Two shots of whiskey contains more alcohol than 2 cans of beer

Time is the only method that works to sober you up. Your liver can only process alcohol at a fixed rate of about 1 drink per hour. Therefore, time is the only way that your body can remove the alcohol from your system - which "sobers" you up. Drinking black coffee or taking a cold shower have no effect on removing alcohol from your system. At 2 beers, a 180 pound person will have a blood alcohol level of .04 which will cause a driver to be less alert, less focused, and lose coordination. One shot of whiskey is identical to one beer with respect to alcohol content.

Which of the following factors is NOT used to determine your safe speed when going down a long steep downgrade? A. Length and steepness of grade B. Weather C. Total weight of the vehicle and cargo D. Time of day

Time of day. To determine your safe speed when going down a long steep downgrade, you need to consider the length and steepness of the grade, the weather, the total weight of the vehicle and cargo, as well as the road conditions.

Which of the following is NOT an appropriate reason to flash your braking lights? A. To warn drivers behind you when you need to slow down B. To alert drivers behind you that there are hazards ahead C. To signal to tailgaters that they are too close to your vehicle D. To warn vehicles approaching you from behind that you are driving slowly

To signal to tailgaters that they are too close to your vehicle. Tricks such as flashing your brake lights or turning on your taillights for tailgaters should be avoided since they are not effective and could lead to a crash. It is, however, a good practice to flash your brake lights to warn other drivers about hazards or if you are driving slowly.

Vehicle handling can become unsafe if the weight is not properly balanced. Hard steering can be caused by A. Too little weight on the driving axles B. Too much weight on the steering axles C. Under loaded front axles D. High center of gravity

Too much weight on the steering axles. Too much weight on the steering axles can cause hard steering, which can damage the steering axle and tires. Too little weight on the driving axles can cause poor traction. Under loaded front axles can make the steering axle too light to steer safely. A high center of gravity may cause the vehicle to tip over.

If you have to turn quickly to avoid a crash, which of the following is the best approach? A. Turn sharply, then brake B. Turn only as much as needed, then counter steer when you have passed the obstacle C. Apply brakes aggressively to slow vehicle down, then turn D. Turn sharply to the right

Turn only as much as needed, then counter steer when you have passed the obstacle. When you need to turn quickly to avoid a crash, it is important that you do not apply the brakes when turning because it is easy to lock your wheels while turning. Also, you should turn only as much as required to clear the obstacle. If you turn sharply, you increase the chance of a skid or rollover. Finally, you should be prepared to counter steer (i.e., turn the wheel back in the other direction) once you've cleared your obstacle.

When backing, what is the best method to use to avoid blind spots? A. Use mirrors on both sides B. Back towards the driver's side, where you can see better C. Look at your path D. Use a helper

Use a helper. This question asks for the*best* method. Although using mirrors on both sides, backing towards the driver's side, and looking at your path are good practices when backing, the *best* method is to use a helper.

If you have an electrical equipment fire or a gasoline or oil fire, you can____? A. Use a type B:C fire extinguisher only B. Use water C. Use a type A:B:C or B:C fire extinguisher D. Use a type D fire extinguisher only

Use a type A:B:C or B:C fire extinguisher. This is an example of question that calls for the best answer, so be sure to read all answer choices carefully before responding. For electrical or gasoline/oil fires, either a B:C or a A:B:C fire extinguisher can be used. Answer choice A is not correct because it says that *only* a B:C fire extinguisher could be used. Water should not be used on these types of fires because it can cause shock or spread the flames.

________ can cause lack of braking power, wheel lockups, pulling to one side or the other, and jackknifing. A. Overheated tires B. Bleeding tar C. Wet brakes D. Loose engine belts

Wet brakes. Wet brakes can occur when driving in heavy rain or through standing water. Water on your brakes may cause your brakes to grab or lose their stopping power, which may lead to wheel lockups, pulling to one side or jackknifing.

If you are transporting cargo, you should inspect the cargo and securing devices A. Within the first 50 miles of driving B. Before the trip C. During every driving brake on the trip D. Before the trip, within 50 miles after beginning the trip, and at least every 150 miles or 3 hours

Before the trip, within 50 miles after beginning the trip, and at least every 150 miles or 3 hours. It is important to inspect the cargo and securing devices both before and during your trip.

Cargo such as dry bulk or hanging meat A. Require no special driving attention B. Have high centers of gravity and are unstable loads C. Require special transit permits D. Have low centers of gravity and can lean on curves

Have high centers of gravity and are unstable loads. Because dry bulk or hanging meat have high centers of gravity, they require caution going around curves or making sharp turns. They do not require special transit permits (unless over-length, over-width, or overweight).

Operating a motor vehicle with the intent of doing harm to others or physically assaulting a driver or their vehicle is known as? A. Aggressive driving B. Defensive driving C. Tailgating D. Road rage

Road rage. Road rage occurs when a drivers displays actions that are intended to cause violence or harm to other drivers. It is a more extreme case of aggressive driving because there is intent to injure or cause harm.

Which contains more alcohol: a 12-ounce glass of 5% beer, a 5-ounce glass of 12% wine or a 1 1/2-ounce shot of 80 proof liquor. A. 12-ounce glass of 5% beer B. 5-ounce glass of 12% wine C. 1 1/2-ounce shot of 80 proof liquor D. They all contain the same amount of alcohol

They all contain the same amount of alcohol. Each of these drink amounts contain the same amount of alcohol.

Where should you place your reflectors when stopped on a one-way or divided highway? A. 10', 100', 200' toward approaching traffic B. 100' ahead, 100' behind and 10' toward approaching traffic C. 10', 50', 100' toward approaching traffic D. 10' ahead, 10' behind and 100' behind your vehicle

10', 100', 200' toward approaching traffic. On a one-way road, it is important that you place all three reflectors toward approaching traffic (this eliminates answers B and D). Answer A is correct because you want to place the furthest reflector 200' toward approaching traffic to insure that any approaching vehicles have enough time to react.

Where should you place your reflectors when stopped on a un-divided highway or two lane road carrying traffic in both directions? A. 10' ahead, 10' behind and 100' toward approaching traffic B. 10', 100', 200' toward approaching traffic C. 10', 50', 100' behind your vehicle D. 100' behind and ahead of your vehicle and within 10' of the front or rear corner

100' behind and ahead of your vehicle and within 10' of the front or rear corner. When stopped on a road that is carrying traffic in both directions, it is important that you place reflectors both ahead of and behind your vehicle (this eliminates answers B, C).

How long does it take a typical tractor-trailer to clear a double railroad track? A. 15 seconds B. 7 seconds C. 1 minute D. 30 seconds

15 seconds. It takes a typical tractor-trailer about 14 seconds to clear a single railroad track and more than 15 seconds to clear a double track.

You should check your tires every ____ or every ____ when driving in very hot weather. A. 1 hour, 50 miles B. 2 hours, 100 miles C. 3 hours, 200 miles D. 5 hours, 250 miles

2 hours, 100 miles. Hotter temperatures increase air pressure. If you check your tires and they are too hot to touch, you should remain stopped until they cool off. Overheated tires may blow out or catch fire.

You are driving a 50 foot truck at 38 MPH, how much space (in seconds) should you keep in front of you? A. 3 seconds B. 6 seconds C. 4 seconds D. 5 seconds

5 seconds. To calculate your space required, use the following formula: If going under 40 MPH, use 1 second for each 10' of vehicle length. If going over 40 MPH, use the same formula but add 1 second. In this scenario, a 50' truck requires 5 seconds, and you don't need to add an additional second, because you are travelling under 40 mph.

The average person requires how many hours of sleep per 24 hour period? A. 7 or 8 B. 8 or 9 C. 6 or 7 D. 5 or 6

7 or 8. The average person requires 7 or 8 hours of sleep per 24 hour period. If your body does not get the sleep that it requires, you may become very drowsy and fall asleep without even knowing it.

You are driving a 60 foot truck at 55 MPH, how much space (in seconds) should you keep in front of you? A. 5 seconds B. 6 seconds C. 7 seconds D. 8 seconds

7 seconds. To calculate your space required, use the following formula: If going under 40 MPH, use 1 second for each 10' of vehicle length. If going over 40 MPH, use the same formula but add 1 second. In this scenario, a 60' truck requires 6 seconds, but you need to add an additional second, because you are travelling over 40 mph. So the correct answer is 7 seconds.

It is important for driving safety to always be looking ahead. Which of the following is NOT a recommended time/distance that you should be looking ahead? A. About 12-15 seconds B. About one block for city driving C. About 1/4 mile for open highway driving D. About 5 car lengths on the highway

About 5 car lengths. It is important to look ahead about 12-15 seconds to insure you have adequate time to stop or change lanes if necessary. 12 to 15 seconds is equivalent to about one city block or 1/4 mile on the open highway. Looking ahead 5 car lengths (about 70 feet) will not give you adequate time to react.

When driving in very hot temperatures, you should: A. Check your tires every 2 hours or every 100 miles B. Let your tires cool down (remain stopped) if they are too hot to touch C. Insure that you have enough antifreeze in the system D. All of the above

All of the above. When driving in extreme heat it is important to check your tires every 2 hours or 100 miles. If the tires are too hot to touch, you should remain stopped until they cool off. You should also insure that you have enough antifreeze in the system.

Which of the following are potential suspension system defects? A. Leaking shock absorbers B. Cracked or broken spring hangers C. Broken leaf in a spring D. All of the above

All of the listed answers are potential suspension system defects.

The act of operating a motor vehicle in a selfish, bold, or pushy manner, without regard for the rights or safety of others is known as? A. Defensive driving B. Road rage C. Aggressive driving D. Distracted driving

An aggressive driver is only concerned with their driving and not others on the road. Road rage differs from aggressive driving because with Road Rage, the driver shows intent to harm others.

With the controlled braking method, you _____? A. Lightly apply braking pressure B. Apply the brakes as hard as you can without locking the wheels C. Apply the brakes all the way until the wheels lock up, release the brakes and apply them again when the wheels start to roll again D. Repeatedly tap the brakes as fast as you can

Apply the brakes as hard as you can without locking the wheels. In addition, you should keep your steering movements very small while using a "controlled braking" method.

If you are stopped on an incline, how can you start moving without rolling back? A. Shift to neutral B. Fully engage the clutch B. Apply the parking brake D. Aggressively pump the accelerator

Apply the parking brake. Applying the parking brake will keep the vehicle from rolling. Engaging the clutch or shifting to neutral will cause the vehicle to roll backwards. Rough acceleration may cause mechanical damage or damage the coupling if pulling a trailer.

When backing your vehicle, which of the following is NOT recommended. A. Back as slow as possible B. Back towards the right side C. Use the lowest reverse gear D. Back and turn towards the driver's side

Back towards the right side. When backing your vehicle you should always back and turn towards the driver's side, even if it means going around the block to put your vehicle in the right position. Backing towards the right side is very dangerous because you can not see well.

Which of the following is a condition in which you should downshift? A. Before starting down a hill B. Before accelerating C. After starting down a hill D. After starting up a hill

Before starting down a hill. Before you start down a hill, you should slow down and shift to a speed that is controllable without using the brakes too hard. Answers C and D are wrong because you should downshift before starting up or down a hill.

Which of the following is NOT an important reason to look far ahead when you are driving? A. Look for vehicles coming into your lane B. Determine if there are any hills coming up C. Look for brake lights from slowing vehicles D. Determine if there are any upcoming traffic lights that might require you to stop

Determine if there are any hills coming up. Safety is the number one reason that it is important that you be looking ahead when driving. Answers A, C, and D are all important safety reasons.

Which of the following represents the best way to make a right turn if you have a large vehicle that cannot make the turn without swinging into another lane. CDL-right-turn Diagram A Diagram B Diagram C Diagram D

Diagram C. If you must swing into another lane when making a right turn, it is important to keep the vehicle close to the curb so that other vehicles do not try and pass you to the right (because they think you are turning left). In answers A, B, and D the path shows the vehicle going into the left lanes which make it appear to be turning left.

Which of the following are possible causes of tire fires? A. Loose fuel connections or under-inflated tires B. Dual tires that touch and under-inflated tires C. Improperly loaded cargo and dual tires that touch D. Poor cargo ventilation or short circuits

Dual tires that touch and under-inflated tires. Duals that touch and under-inflated tires can lead to tires becoming overheated and catching on fire.

Shifting into a lower gear and removing your foot off of the accelerator to slow your vehicle is known as? A. Double clutching B. Engine braking C. Anti-lock braking D. Brake fade

Engine braking. Engine braking is critical to use on long steep downgrades to help slow your vehicle and removing your dependence on your braking system.

Which of the following is NOT a basic step to be taken at a crash scene? A. Notify authorities B. Care for the injured C. Gather the contact information of all the drivers involved D. Protect the area

Gather the contact information of all the drivers involved. If you are involved in a crash and are not seriously hurt, your first priority is to take steps to prevent further damage and injury. These steps include protecting the area, notifying authorities, and caring for the injured. Gathering contact information is not a priority.

If you feel yourself becoming drowsy when you are driving, you should: A. Drink coffee or other product that contains caffeine B. Get off the road and get some sleep C. Open the window to let air in D. All of the above

Get off the road and get some sleep. If you feel yourself becoming drowsy, the only safe course of action is to stop driving and get sleep. Other methods (e.g., caffeine, opening windows, radio) are not recommended because they ultimately don't counteract the body's need for sleep.

Which of the following is NOT a required emergency equipment must you have? A. Fire extinguisher B. Warning devices for parked vehicles C. Glass breaking device D. Spare electrical fuses (or circuit breakers)

Glass breaking device. Vehicles must be equipped with fire extinguishers, warning devices (e.g., reflective warning triangles, and spare electrical fuses (unless the vehicle is equipped with circuit breakers)

Which of the following statements is FALSE? A. You can almost always turn to miss an obstacle more quickly than you can stop B. Stopping is not always the safest thing to do in an emergency C. If a tire blows, you should put the brakes on hard to stop quickly D. Antilock Braking Systems (ABS) only activate when wheels are about to lock

If a tire blows, you should put the brakes on hard to stop quickly. This statement is FALSE. If a tire blows, you should hold the steering wheel firmly, stay off the brake until the vehicles slows, and check the tires when the vehicle comes to a complete stop.

Which of the following approaches is advised for dealing with tailgaters? A. Quickly change your lane B. Increase your following distance by getting farther away from the vehicles ahead of you C. Speed up D. Flash your brake lights

Increase your following distance by getting farther away from the vehicles ahead of you If you are being tailgated, you should increase your following distance (the distance between your vehicle and the vehicles ahead of you) to help you avoid having to make sudden changes and to allow the tailgater room to get around you.

When using a helper for backing, what is the most important hand signal that you and the helper should agree on? A. Stop B. Turn harder left C. Turn harder right D .Go slower

It is important that you and your helper both agree on the same hand signal for stop.

Which of the following is NOT a recommended action to take when confronted by an aggressive driver? A. Ignore them and refuse to react to any of their gestures B. Make eye contact and motion to them that you are calling the authorities C. Make every attempt to get out of their way D. Do not let your pride and ego affect your actions

Make eye contact and motion to them that you are calling the authorities. If you are confronted by an aggressive driver you should not take any actions which could aggravate the situation. Specifically, you should not make eye contact with the driver or gesture to them.