#1 CDL Practice Test General Knowledge for ALL 50 States – 2023 Update
To help you prepare for the CDL General Knowledge test, we have created this practice test consisting of 50 questions. Each question is worth two points for a total of 100 possible points. A passing score is 80%. We have created both a General Knowledge Practice Quiz and a General Knowledge Practice Test.
The General Knowledge Practice Quiz reveals the correct answer during each question to help you study for the actual General Knowledge test. The General Knowledge Practice Test doesn’t reveal the correct answers until the test is over. The questions and answers are given in random order each time you retake the test. When you are finished testing, simply click on the “Get Results” button to see your test results. Clicking on the blue “List” button will reveal a list of all the questions you answered correctly and incorrectly. To take the test again, just refresh your browser window. It’s that easy.
Press the start button to begin your free General Knowledge Practice Quiz. Good luck!
General Knowledge CDL Practice Quiz
Question 1 |
A | use only water in the cooling system. |
B | check the coolant level of a hot engine. |
C | use windshield washer fluid as coolant. |
D | safely remove the radiator cap and add coolant while the engine is hot. |
Question 2 |
A | Electrical fire. |
B | None of these fires can be safely extinguished by water. |
C | Grease fire. |
D | Gasoline fire. |
Question 3 |
A | under-inflated tires, dual tires that touch |
B | over-heated brakes, under-inflated tires |
C | poor-quality retreads, under-inflated tires |
D | dual tires that touch, hot road surfaces |
Question 4 |
A | before operating the vehicle. |
B | at least once a week. |
C | whenever you stop to refuel. |
D | if any problems occurred the last the time the vehicle was operated. |
Question 5 |
A | none of these. |
B | five or more. |
C | seven or more. |
D | three or more. |
Question 6 |
A | need less space ahead than full trucks |
B | have the same stopping distance as full trucks |
C | have better traction when stopping than full trucks |
D | require greater stopping distance than full trucks |
Question 7 |
A | Perception distance, reaction distance, and braking distance. |
B | Observation distance, reaction distance, and slowing distance. |
C | Perception distance, response distance, and reaction distance. |
D | Perception distance, slowing distance, and braking distance. |
Question 8 |
A | fishtailing. |
B | offtracking. |
C | sidetracking. |
D | slidetracking. |
Question 9 |
A | depends on the service brakes being in adjustment. |
B | increases when the service brakes are hot. |
C | decreases when the service breaks are hot. |
D | is not affected by the condition of the service brakes. |
Question 10 |
A | keep the cargo as close to the ground as possible. |
B | keep two hands firmly planted on the steering wheel at all times. |
C | downshift into the turn. |
D | check to make sure that the brakes are properly balanced. |
Question 11 |
A | half |
B | three times |
C | two times |
D | four times |
Question 12 |
A | loose fuel connections |
B | both loose fuel connections and under inflated tires |
C | under inflated tires |
D | eating spicy food in the truck cab |
Question 13 |
A | four |
B | three |
C | two |
D | one |
Question 14 |
A | it will be raised slightly when the tractor is backed under it. |
B | the end of the kingpin is at waist level. |
C | the end of the kingpin is even with the top of the fifth wheel. |
D | the kingpin is about 1¼ inches above the fifth wheel. |
Question 15 |
A | the lug nut needs to be replaced. |
B | the lug nut is cheap. |
C | the lug nut is loose. |
D | the wheel needs cleaning. |
Question 16 |
A | rust |
B | burning |
C | leaks |
D | rubbing |
Question 17 |
A | because law enforcement may inspect your vehicle on the road. |
B | to ensure safety for yourself, your passengers, and other drivers. |
C | because it is a requirement for all drivers. |
D | to help ensure the vehicle will make it to your destination. |
Question 18 |
A | Because some liquids expand more than others when they get warm. |
B | Because some of the heaviest liquids don’t need any. |
C | Because tank baffles are not always legal with outage. |
D | Because it's good to know that information. |
Question 19 |
A | A stopped transit bus. |
B | Pedestrians and bicyclists. |
C | Road construction zones. |
D | All of these are considered a hazard. |
Question 20 |
A | to avoid mixing hazmat with food. |
B | to warn others of hazardous materials. |
C | to combat terrorism. |
D | to make your vehicle look official. |
Question 21 |
A | you are driving on the freeway. |
B | you are driving on hilly, rural roads. |
C | road conditions are excellent. |
D | the road is wet, icy, or snow covered. |
Question 22 |
A | you have to push harder and harder to get the same stopping power on a downgrade. |
B | there is a slight vibration when you press down on the brake pedal. |
C | the brake pedal feels firm when you apply pressure. |
D | you release pressure on the brake pedal and speed increases. |
Question 23 |
A | a dry bulk tank should only be filled halfway. |
B | the load can shift. |
C | the load can catch fire easily. |
D | the load should not get wet. |
Question 24 |
A | keep your high beams on at all times. |
B | roll down your window so that the fresh air will help keep you awake. |
C | drink coffee or other caffeine products to help keep you awake. |
D | make sure you are driving slow enough so you can stop within the range of your headlights in case of an emergency. |
Question 25 |
A | 5/32-inch in every major groove. |
B | 3/32-inch in every major groove. |
C | 2/32-inch in every major groove. |
D | 4/32-inch in every major groove. |
Question 26 |
A | The drinker's brain is increasingly affected. |
B | All of these things happen. |
C | Muscle control and coordination are affected. |
D | Judgment and self-control are the first to be affected. |
Question 27 |
A | Load more weight over the drive axle for better traction. |
B | Load more cargo toward the front of the truck for a full load. |
C | Load cargo weight evenly over all the axles. |
D | Load cargo toward the rear of the truck for easier unloading. |
Question 28 |
A | three inches |
B | one inch |
C | two inches |
D | one half inch |
Question 29 |
A | Greater stopping distance. |
B | The same amount of stopping distance. |
C | Shorter stopping distance. |
D | It depends on what mood you are in at the time. |
Question 30 |
A | roll down the windows. |
B | slap yourself in the face three times. |
C | turn up the radio. |
D | stop to sleep. |
Question 31 |
A | before starting down a hill and before going up a hill. |
B | before starting down a hill and before entering a curve. |
C | before going up a hill and before entering a curve. |
D | before starting down a hill and before entering a tunnel. |
Question 32 |
A | the trailer is out of brake adjustment. |
B | the trailer is being hauled at high speed. |
C | the trailer is empty or lightly loaded. |
D | the trailer is fully loaded or very heavy. |
Question 33 |
A | driving too slow for road conditions. |
B | driving too fast for road conditions. |
C | bad tires. |
D | poorly adjusted brakes. |
Question 34 |
A | start the turn, then back up to re-position |
B | turn right and drive over the curb |
C | turn wide as you complete the turn |
D | turn wide before you start the turn |
Question 35 |
A | Move forward slowly and push firmly on the brake pedal. |
B | Push the brake pedal firmly 5 seconds; listen for leaks. |
C | Pump the brake pedal 5 times; push the pedal firmly 3 seconds; the pedal should not move. |
D | Pump the brake pedal 3 times; push the pedal firmly 5 seconds; the pedal should not move. |
Question 36 |
A | A minimum of three. |
B | A minimum of one. |
C | A minimum of four. |
D | A minimum of two. |
Question 37 |
A | Put your warning devices out within 15 minutes. |
B | Turn on your 4-way emergency flashers to warn other drivers. |
C | Warn other drivers by using your left turn signal lights. |
D | Keep your low beam lights on. |
Question 38 |
A | The same amount of space you would at night. |
B | One vehicle length for every 10,000 lb. of gross vehicle weight. |
C | More space than is needed for ideal driving conditions. |
D | The same amount of space you would on a dry road. |
Question 39 |
A | Downshift after you are in the curve. |
B | Turn on your four-way flashers as you approach the offramp. |
C | Slow to a safe speed before the curve. |
D | Nothing, because the posted speed limit for the offramp is usually 10 miles per hour below the safe speed limit for the offramp. |
Question 40 |
A | rolled down windows |
B | sunglasses |
C | rear view cameras |
D | mirrors |
Question 41 |
A | the weight of the liquid. |
B | both of these. |
C | the legal weight limits. |
D | neither of these. |
Question 42 |
A | it is absolutely necessary. |
B | you will be parked for a short time. |
C | there is ice and snow, to prevent skidding. |
D | testing the trailer brakes after hooking up to a trailer. |
Question 43 |
A | tunnels, overpasses |
B | vehicles, traffic signs |
C | law enforcement officers, detours |
D | truck stops, gas stations |
Question 44 |
A | Play in the steering wheel of more than five degrees. |
B | Oil on the tie rod. |
C | Play in the steering wheel of more than ten degrees (two inches on a 20-inch steering wheel). |
D | Too many vertical stacks. |
Question 45 |
A | To prevent others from distracting you. |
B | To direct traffic away from you. |
C | To watch for steering errors. |
D | To see the blind spots you can't see. |
Question 46 |
A | Shift the truck into neutral and coast down the hill to save gas. |
B | Use a lower gear than you would use to climb the hill. |
C | Use the same gear you would use to climb the hill. |
D | Use a higher gear than you would use to climb the hill. |
Question 47 |
A | placard numbers match the seal numbers. |
B | seal is secure. |
C | load is properly secured. |
D | seal is authentic. |
Question 48 |
A | exempt from hazardous materials restrictions. |
B | generally used when freight is carried part way by rail or ship. |
C | exempt from weight limit restrictions. |
D | exempt from height restrictions. |
Question 49 |
A | you want to have time to act before it turns into an emergency. |
B | you want to avoid doing something all of a sudden. |
C | it is a federal law. |
D | you want to have a plan to communicate the risk. |
Question 50 |
A | Using your CB radio or cell phone to inform others. |
B | Using turn signals, 4-way flashers, headlights, and the horn. |
C | Using hand signals. |
D | Using a helper when backing up. |
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31 | 32 | 33 | 34 | 35 |
36 | 37 | 38 | 39 | 40 |
41 | 42 | 43 | 44 | 45 |
46 | 47 | 48 | 49 | 50 |
End |
Remember, the General Knowledge Practice Test doesn’t reveal the correct answers until the test is over. The questions and answers are given in random order each time you retake the test. When you are finished testing, simply click on the “Get Results” button to see your test results. Clicking on the blue “List” button will reveal a list of all the questions you answered correctly and incorrectly. To take the test again, just refresh your browser window.
Press the start button to begin your free General Knowledge Practice Test. Good luck!
General Knowledge CDL Practice Test
Question 1 |
A | at least once a week. |
B | if any problems occurred the last the time the vehicle was operated. |
C | whenever you stop to refuel. |
D | before operating the vehicle. |
Question 2 |
A | before starting down a hill and before entering a curve. |
B | before starting down a hill and before entering a tunnel. |
C | before starting down a hill and before going up a hill. |
D | before going up a hill and before entering a curve. |
Question 3 |
A | leaks |
B | burning |
C | rubbing |
D | rust |
Question 4 |
A | Slow to a safe speed before the curve. |
B | Downshift after you are in the curve. |
C | Turn on your four-way flashers as you approach the offramp. |
D | Nothing, because the posted speed limit for the offramp is usually 10 miles per hour below the safe speed limit for the offramp. |
Question 5 |
A | roll down the windows. |
B | stop to sleep. |
C | turn up the radio. |
D | slap yourself in the face three times. |
Question 6 |
A | the end of the kingpin is at waist level. |
B | it will be raised slightly when the tractor is backed under it. |
C | the end of the kingpin is even with the top of the fifth wheel. |
D | the kingpin is about 1¼ inches above the fifth wheel. |
Question 7 |
A | increases when the service brakes are hot. |
B | is not affected by the condition of the service brakes. |
C | decreases when the service breaks are hot. |
D | depends on the service brakes being in adjustment. |
Question 8 |
A | the weight of the liquid. |
B | neither of these. |
C | both of these. |
D | the legal weight limits. |
Question 9 |
A | three times |
B | two times |
C | half |
D | four times |
Question 10 |
A | two |
B | three |
C | one |
D | four |
Question 11 |
A | to warn others of hazardous materials. |
B | to avoid mixing hazmat with food. |
C | to make your vehicle look official. |
D | to combat terrorism. |
Question 12 |
A | A stopped transit bus. |
B | All of these are considered a hazard. |
C | Road construction zones. |
D | Pedestrians and bicyclists. |
Question 13 |
A | Push the brake pedal firmly 5 seconds; listen for leaks. |
B | Move forward slowly and push firmly on the brake pedal. |
C | Pump the brake pedal 5 times; push the pedal firmly 3 seconds; the pedal should not move. |
D | Pump the brake pedal 3 times; push the pedal firmly 5 seconds; the pedal should not move. |
Question 14 |
A | two inches |
B | one half inch |
C | three inches |
D | one inch |
Question 15 |
A | vehicles, traffic signs |
B | tunnels, overpasses |
C | truck stops, gas stations |
D | law enforcement officers, detours |
Question 16 |
A | Keep your low beam lights on. |
B | Warn other drivers by using your left turn signal lights. |
C | Put your warning devices out within 15 minutes. |
D | Turn on your 4-way emergency flashers to warn other drivers. |
Question 17 |
A | keep your high beams on at all times. |
B | roll down your window so that the fresh air will help keep you awake. |
C | make sure you are driving slow enough so you can stop within the range of your headlights in case of an emergency. |
D | drink coffee or other caffeine products to help keep you awake. |
Question 18 |
A | a dry bulk tank should only be filled halfway. |
B | the load can shift. |
C | the load can catch fire easily. |
D | the load should not get wet. |
Question 19 |
A | the wheel needs cleaning. |
B | the lug nut is cheap. |
C | the lug nut needs to be replaced. |
D | the lug nut is loose. |
Question 20 |
A | have better traction when stopping than full trucks |
B | have the same stopping distance as full trucks |
C | require greater stopping distance than full trucks |
D | need less space ahead than full trucks
|
Question 21 |
A | none of these. |
B | seven or more. |
C | five or more. |
D | three or more. |
Question 22 |
A | you will be parked for a short time. |
B | there is ice and snow, to prevent skidding. |
C | it is absolutely necessary. |
D | testing the trailer brakes after hooking up to a trailer. |
Question 23 |
A | both loose fuel connections and under inflated tires |
B | underinflated tires |
C | overinflated tires |
D | loose fuel connections |
Question 24 |
A | 3/32-inch in every major groove. |
B | 2/32-inch in every major groove. |
C | 5/32-inch in every major groove. |
D | 4/32-inch in every major groove. |
Question 25 |
A | Grease fire. |
B | None of these fires can be safely extinguished by water. |
C | Gasoline fire. |
D | Electrical fire. |
Question 26 |
A | Using hand signals. |
B | Using your CB radio or cell phone to inform others. |
C | Using turn signals, 4-way flashers, headlights, and the horn. |
D | Using a helper when backing up. |
Question 27 |
A | Load cargo toward the rear of the truck for easier unloading. |
B | Load more cargo toward the front of the truck for a full load. |
C | Load cargo weight evenly over all the axles. |
D | Load more weight over the drive axle for better traction. |
Question 28 |
A | One vehicle length for every 10,000 lb. of gross vehicle weight. |
B | The same amount of space you would on a dry road. |
C | The same amount of space you would at night. |
D | More space than is needed for ideal driving conditions. |
Question 29 |
A | slidetracking. |
B | sidetracking. |
C | offtracking. |
D | fishtailing. |
Question 30 |
A | Observation distance, reaction distance, and slowing distance. |
B | Perception distance, slowing distance, and braking distance. |
C | Perception distance, reaction distance, and braking distance. |
D | Perception distance, response distance, and reaction distance. |
Question 31 |
A | the trailer is being hauled at high speed. |
B | the trailer is out of brake adjustment. |
C | the trailer is empty or lightly loaded. |
D | the trailer is fully loaded or very heavy. |
Question 32 |
A | Oil on the tie rod. |
B | Too many vertical stacks. |
C | Play in the steering wheel of more than ten degrees (two inches on a 20-inch steering wheel). |
D | Play in the steering wheel of more than five degrees. |
Question 33 |
A | Judgment and self-control are the first to be affected. |
B | All of these things happen. |
C | The drinker's brain is increasingly affected. |
D | Muscle control and coordination are affected. |
Question 34 |
A | road conditions are excellent. |
B | you are driving on hilly, rural roads. |
C | the road is wet, icy, or snow covered. |
D | you are driving on the freeway. |
Question 35 |
A | Use a higher gear than you would use to climb the hill. |
B | Use the same gear you would use to climb the hill. |
C | Shift the truck into neutral and coast down the hill to save gas. |
D | Use a lower gear than you would use to climb the hill. |
Question 36 |
A | generally used when freight is carried part way by rail or ship. |
B | exempt from weight limit restrictions. |
C | exempt from height restrictions. |
D | exempt from hazardous materials restrictions. |
Question 37 |
A | To watch for steering errors. |
B | To see the blind spots you can't see. |
C | To direct traffic away from you. |
D | To prevent others from distracting you. |
Question 38 |
A | you want to avoid doing something all of a sudden. |
B | it is a federal law. |
C | you want to have a plan to communicate the risk. |
D | you want to have time to act before it turns into an emergency. |
Question 39 |
A | keep two hands firmly planted on the steering wheel at all times. |
B | keep the cargo as close to the ground as possible. |
C | check to make sure that the brakes are properly balanced. |
D | downshift into the turn. |
Question 40 |
A | mirrors |
B | sunglasses |
C | rolled down windows |
D | rear view cameras |
Question 41 |
A | to help ensure the vehicle will make it to your destination. |
B | because it is a requirement for all drivers. |
C | because law enforcement may inspect your vehicle on the road. |
D | to ensure safety for yourself, your passengers, and other drivers. |
Question 42 |
A | turn right and drive over the curb |
B | start the turn, then back up to re-position |
C | turn wide as you complete the turn |
D | turn wide before you start the turn |
Question 43 |
A | safely remove the radiator cap and add coolant while the engine is hot. |
B | use windshield washer fluid as coolant. |
C | check the coolant level of a hot engine. |
D | use only water in the cooling system. |
Question 44 |
A | placard numbers match the seal numbers. |
B | seal is secure. |
C | load is properly secured. |
D | seal is authentic. |
Question 45 |
A | the brake pedal feels firm when you apply pressure. |
B | you release pressure on the brake pedal and speed increases. |
C | you have to push harder and harder to get the same stopping power on a downgrade. |
D | there is a slight vibration when you press down on the brake pedal. |
Question 46 |
A | A minimum of four. |
B | A minimum of three. |
C | A minimum of one. |
D | A minimum of two. |
Question 47 |
A | poor-quality retreads, under-inflated tires |
B | over-heated brakes, under-inflated tires |
C | under-inflated tires, dual tires that touch |
D | dual tires that touch, hot road surfaces |
Question 48 |
A | poorly adjusted brakes. |
B | bad tires. |
C | driving too slow for road conditions. |
D | driving too fast for road conditions. |
Question 49 |
A | Greater stopping distance. |
B | Shorter stopping distance. |
C | The same amount of stopping distance. |
D | It depends on what mood you are in at the time. |
Question 50 |
A | Because some liquids expand more than others when they get warm. |
B | Because some of the heaviest liquids don’t need any. |
C | Because tank baffles are not always legal with outage. |
D | Because it's good to know that information. |
← |
List |
→ |
1 | 2 | 3 | 4 | 5 |
6 | 7 | 8 | 9 | 10 |
11 | 12 | 13 | 14 | 15 |
16 | 17 | 18 | 19 | 20 |
21 | 22 | 23 | 24 | 25 |
26 | 27 | 28 | 29 | 30 |
31 | 32 | 33 | 34 | 35 |
36 | 37 | 38 | 39 | 40 |
41 | 42 | 43 | 44 | 45 |
46 | 47 | 48 | 49 | 50 |
End |
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