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