CDL - COMBINATION VEHICLE PRACTICE TEST QUESTIONS
AND ANSWERS RECENT UPLOAD
1. What's the most important reason for doing a vehicle inspection? - ANSWER ✔ - Safety
2. What things should you check during a trip? - ANSWER ✔ - instruments, air pressure gauges, temperature
gauges, pressure gauges, voltmeter, mirrors, tires, cargo
3. Name some key steering system parts. - ANSWER ✔ - gear box, tie rods, steering column
4. Name some suspension system defects. - ANSWER ✔ - 1/4 or more of leaves in spring assembly are broken;
any leaf is missing; spring hangers that allow movement of axle from proper position; leaking shock absorbers
5. What 3 kinds of emergency equipment must you have? - ANSWER ✔ - spare electrical fuses, 3 red reflective
triangles, properly charged & rated fire extinguisher
6. What is the minimum tread depth for front tires? - ANSWER ✔ - 4/32"
7. What is minimum tread depth for other tires? - ANSWER ✔ - 2/32"
8. Name some things you should check on the front of your vehicle during the walk-around inspection. - ANSWER
✔ - condition of: front axle, steering system, windshield; lights & reflectors; parking, clearance & identification
lights clean, operating & proper color; reflectors clean & proper color; right front turn signal clean, operating
& proper color
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CDL - COMBINATION VEHICLE
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, 9. What should wheel bearing seals be checked for? - ANSWER ✔ - That they're not leaking
10. How many red reflective triangles should you carry? - ANSWER ✔ - 3
11. How do you test hydraulic brakes for leaks? - ANSWER ✔ - Pump brake pedal 3X, then apply firm pressure to
pedal & hold for 5 seconds. The pedal shouldn't move. It it does, there may be a leak or other problem.
12. Why put the starter switch key in your pocket during the pre-trip inspection? - ANSWER ✔ - To ensure that no
one can start or move the vehicle while you're performing your inspection.
13. Why should you back toward the driver's side? - ANSWER ✔ - So you can see well. Backing toward the right
side is very dangerous because you can't see as well. If you back & turn toward driver's side, you can watch
the rear of your vehicle by looking out the side windows.
14. If stopped on a hill, how can you start moving without rolling back? - ANSWER ✔ - Partly engage the clutch
before taking foot off the brake. Put on parking brake whenever necessary to keep from rolling back. Release
parking brake only when you have applied enough engine power to keep from rolling back. Speed up slowly
& gradually so vehicle doesn't jerk.
15. When backing, why is it important to use a helper? - ANSWER ✔ - There are blind spots you can't see.
16. What's the most important hand signal that you and the helper should agree on? - ANSWER ✔ - Stop
17. What are the 2 special conditions where you should downshift? - ANSWER ✔ - Before starting down a hill &
before entering a curve.
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CDL - COMBINATION VEHICLE
©™
AND ANSWERS RECENT UPLOAD
1. What's the most important reason for doing a vehicle inspection? - ANSWER ✔ - Safety
2. What things should you check during a trip? - ANSWER ✔ - instruments, air pressure gauges, temperature
gauges, pressure gauges, voltmeter, mirrors, tires, cargo
3. Name some key steering system parts. - ANSWER ✔ - gear box, tie rods, steering column
4. Name some suspension system defects. - ANSWER ✔ - 1/4 or more of leaves in spring assembly are broken;
any leaf is missing; spring hangers that allow movement of axle from proper position; leaking shock absorbers
5. What 3 kinds of emergency equipment must you have? - ANSWER ✔ - spare electrical fuses, 3 red reflective
triangles, properly charged & rated fire extinguisher
6. What is the minimum tread depth for front tires? - ANSWER ✔ - 4/32"
7. What is minimum tread depth for other tires? - ANSWER ✔ - 2/32"
8. Name some things you should check on the front of your vehicle during the walk-around inspection. - ANSWER
✔ - condition of: front axle, steering system, windshield; lights & reflectors; parking, clearance & identification
lights clean, operating & proper color; reflectors clean & proper color; right front turn signal clean, operating
& proper color
Page 1 of 11
CDL - COMBINATION VEHICLE
©™
, 9. What should wheel bearing seals be checked for? - ANSWER ✔ - That they're not leaking
10. How many red reflective triangles should you carry? - ANSWER ✔ - 3
11. How do you test hydraulic brakes for leaks? - ANSWER ✔ - Pump brake pedal 3X, then apply firm pressure to
pedal & hold for 5 seconds. The pedal shouldn't move. It it does, there may be a leak or other problem.
12. Why put the starter switch key in your pocket during the pre-trip inspection? - ANSWER ✔ - To ensure that no
one can start or move the vehicle while you're performing your inspection.
13. Why should you back toward the driver's side? - ANSWER ✔ - So you can see well. Backing toward the right
side is very dangerous because you can't see as well. If you back & turn toward driver's side, you can watch
the rear of your vehicle by looking out the side windows.
14. If stopped on a hill, how can you start moving without rolling back? - ANSWER ✔ - Partly engage the clutch
before taking foot off the brake. Put on parking brake whenever necessary to keep from rolling back. Release
parking brake only when you have applied enough engine power to keep from rolling back. Speed up slowly
& gradually so vehicle doesn't jerk.
15. When backing, why is it important to use a helper? - ANSWER ✔ - There are blind spots you can't see.
16. What's the most important hand signal that you and the helper should agree on? - ANSWER ✔ - Stop
17. What are the 2 special conditions where you should downshift? - ANSWER ✔ - Before starting down a hill &
before entering a curve.
Page 2 of 11
CDL - COMBINATION VEHICLE
©™
