Commercial Drivers License General Knowledge Test
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Passing grade - 10 errors or less.

1. CDL medical certificates must be renewed every:

2. Merging onto a road is safest if you:

3. What three things add up to the total stopping distance for your truck or bus?

4. You are checking your steering and exhaust systems in a pre-trip inspection. Which of these problems, if found, should be fixed before the vehicle is driven?

5. How does weight affect stopping?

6. When the roads are slippery, you should:

7. Which of these is NOT a good rule to follow when caring for injured at an accident scene?

8. You are driving on a straight, level highway at 50 mph. There are no vehicles in front of you. Suddenly a tire blows out on your vehicle. What should you do first?

9. After starting the engine, the:

10. You are driving a heavy vehicle with a manual transmission. You have to stop the vehicle on the shoulder while driving on an uphill grade. Which of these is a good rule to follow when putting it back in motion?

11. Which of these statements about speed management is true?

12. Where must you keep shipping papers when transporting hazardous materials?

13. You should use your mirrors to check:

14. Extra care is needed to keep your vehicle centered in your lane because commercial vehicles:

15. Why is a broken exhaust system dangerous?

16. Which of these statements about causes of vehicle fires is true?

17. The purpose of retarders is to:

18. Which of these is especially true about your tires in hot weather?

19. Which of these is usually true about driving in tunnels?

20. When driving through work zones, you should:

21. When you are passing another vehicle, pedestrian, or bicyclist, you should assume that they:

22. If you are not sure what to use to put out a hazardous material fire, you should:

23. What should you do when your vehicle hydroplanes?

24. Which of these is true regarding the use of drugs while driving?

25. Which of these statements about brakes is true?

26. You are driving a new truck with a manual transmission. What gear will you probably have to use to take a long, steep, downhill grade?

27. Which of these statements about certain types of cargo is true?

28. Which of these statements about marking a stopped vehicle is true?

29. Which of these is true about rear drive wheel braking skids?

30. Which of these statements about double clutching and shifting is true?

31. Which of these is true about your overhead clearance?

32. How far should a driver look ahead of the vehicle while driving?

33. If you need to leave the road in a traffic emergency, you should:

34. Which of these statements about backing a heavy vehicle is NOT true?

35. Which of these lights cannot be checked at the same time?

36. Which of these is correct about emergency or evasive action?

37. You are driving a vehicle that could safely be driven at 55 mph on an open road. But traffic is now heavy, moving at 35 mph, in a 55 mph zone. The safest speed for your vehicle is most likely:

38. According to the Commercial Driver Supplement, why should you limit the use of your horn?

39. Which of these is true about bad weather and driving conditions?

40. To determine blood alcohol concentration (BAC) for a person, it is neccessary to know:

41. Which of these happens when a tire blows out at highway speed?

42. You are driving a 40 foot vehicle at 35 mph. The road is dry and visibility is good. What is the least amount of space that you should keep in front of your vehicle to be safe?

43. Truck escape ramps:

44. Your brakes can get wet when you drive through a heavy rain. What can this cause when the brakes are applied?

45. If you are being tailgated, you should:

46. When driving in cold weather, your tire tread should:

47. Which of these statements about staying alert to drive is true?

48. You are checking your brakes and suspension system for a pre-trip inspection. Which of these statements is true?

49. For a first offense of driving a commercial vehicle under the influence of alcohol or drugs, you will lose your CDL for at least:

50. A full stop is required at a railroad grade crossing when:

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