Safe Driving Practices

Study questions with answers

8 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. If you need steadily more application pressure just to hold the same speed on level ground, the brakes are most likely:

   Correct answer: fading

   Rising application pressure to keep one speed is a sign of brake fade; the driver should ease off, slow down, and shift to a lower gear.

   Source: Section 5.1.10 - Application Pressure Gauge

2. 2. What is the main job of the air compressor?

   Correct answer: To pump air into the storage tanks

   The compressor, driven off the engine by gears or a belt, forces air into the storage tanks (reservoirs) that feed the brakes.

   Source: Section 5.1.1 - Air Compressor

3. 3. Which foundation brake design is found most often at each wheel of an air-brake vehicle?

   Correct answer: The s-cam drum brake

   Foundation brakes sit at every wheel, and the s-cam drum type is by far the most common. Wedge and disc designs exist but are seen less often.

   Source: Section 5.1.8 - Foundation Brakes

4. 4. When you press the pedal on an s-cam brake, what does the extended chamber push rod do first?

   Correct answer: It moves the slack adjuster, which twists the brake camshaft

   Air entering the chamber pushes the rod, which swings the slack adjuster and rotates the camshaft; that turns the S-shaped cam to spread the shoes against the drum.

   Source: Section 5.1.8 - S-cam Brakes

5. 5. On a long, steep downgrade, the wheel brakes should be used mainly to:

   Correct answer: add to the slowing effect of the engine

   On a grade the brakes only supplement engine braking. You should already be in a low gear before you start down the hill.

   Source: Section 5.4.6 - Proper Braking Technique

6. 6. Using the recommended downgrade braking pattern, roughly how long should each brake application last?

   Correct answer: About three seconds

   You brake hard enough to feel a clear slowdown, then release once you are a few mph below your safe speed; that single application should run about three seconds.

   Source: Section 5.4.6 - Proper Braking Technique

7. 7. What physically causes brake fade when the brakes overheat?

   Correct answer: Chemical changes in the lining reduce friction while the drums expand away from the shoes

   Excess heat alters the lining so it grips less, and it swells the drums so the shoes must travel farther and press with less force.

   Source: Section 5.4.5 - Brake Fading or Failure

8. 8. During a normal stop with a manual transmission, you should press the clutch only when:

   Correct answer: engine speed has dropped close to idle

   Keeping the clutch out until the engine winds down near idle helps you make a smooth, controlled stop before you select your starting gear.

   Source: Section 5.4.1 - Normal Stops