Safe Driving Practices

Study questions with answers

12 sample Safe Driving Practices questions with the correct answer, a short explanation, and the official handbook reference. Read through them, then take the quiz above.

1. 1. How far ahead does the manual say good drivers usually look?

   Correct answer: About 12 to 15 seconds ahead

   Most good drivers look 12 to 15 seconds ahead — about one block at low speed and roughly a quarter mile at highway speed.

   Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Seeing Ahead)

2. 2. What is the minimum tread depth required in the grooves of tires other than the front tires?

   Correct answer: 2/32 inch

   Tires other than the front (steering) tires must have at least 2/32 inch of tread depth.

   Source: Pennsylvania CDL Manual — Section 2: Driving Safely (What to Look For)

3. 3. How do objects appear when viewed in a convex ('fisheye' or 'spot') mirror?

   Correct answer: Smaller and farther away than they really are

   A convex mirror gives a wider field of view, but everything looks smaller and seems farther away than it really is.

   Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Seeing to the Sides and Rear)

4. 4. If your vehicle begins to hydroplane, what is the correct response?

   Correct answer: Release the accelerator and push in the clutch

   To recover from hydroplaning, ease off the accelerator and depress the clutch; the brakes should not be used to reduce speed.

   Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Identifying Slippery Surfaces)

5. 5. After driving through deep standing water, how should you dry out wet brakes?

   Correct answer: Apply light brake pressure while driving slowly to heat and dry them

   Apply light pressure on the brakes while driving slowly in a low gear for a short distance to heat and dry them, then make a test stop.

   Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Wet Brakes)

6. 6. How many red reflective triangles must you carry as emergency warning devices?

   Correct answer: Three reflective triangles

   You must carry warning devices for stopped vehicles: three reflective triangles, or at least six fusees or three liquid-burning flares.

   Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Emergency Equipment)

7. 7. What is the minimum tread depth required in every major groove of a front (steering) tire?

   Correct answer: 4/32 inch

   Front tires must have at least 4/32 inch of tread depth in every major groove.

   Source: Pennsylvania CDL Manual — Section 2: Driving Safely (What to Look For)

8. 8. When should you turn a speed retarder off?

   Correct answer: When the pavement is wet, snowy, or icy

   Switch the retarder off any time the pavement is wet, snowy, or icy, since poor traction lets it send the drive wheels into a skid.

   Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Retarders)

9. 9. According to the manual, what is the best advice for driving in fog?

   Correct answer: Avoid driving and pull off until visibility improves

   The manual's best advice for fog is simply not to drive; better to pull off at a truck stop or rest area and wait for visibility to get better.

   Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Driving in Fog)

10. 10. During the seven-step inspection, why do you take the ignition key with you when checking the lights?

    Correct answer: So no one can move the vehicle while you are around or under it

    You take the key so no one else can move the truck while you are outside walking around or under it.

    Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Seven-step Inspection Method)

11. 11. What is 'black ice'?

    Correct answer: A thin, clear layer of ice that makes the road look wet

    Black ice is a thin, clear layer of ice through which you can see the road, making the pavement simply look wet.

    Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Identifying Slippery Surfaces)

12. 12. How much steering-wheel play indicates that a vehicle may be hard to steer?

    Correct answer: More than 10 degrees of play

    Steering-wheel play over 10 degrees — about two inches of movement measured at a 20-inch wheel's rim — makes the vehicle hard to steer.

    Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Steering System Defects)