CDL Practice Test

CDL Safe Driving Practice Questions

Safe Driving makes up 9 of every 50 questions on a Tigertest CDL practice test. Here are 10 of the 80 questions on it, each with the answer and the reason.

Updated 2026-11-10 by the Tigertest team. Covers the CDL general knowledge exam. 80% to pass on the real test.

1. 1. What is the minimum following distance rule for commercial vehicles?

   • A.Four seconds behind the vehicle ahead, adjusted for road surface conditions
   • B.One second for every 10 feet of vehicle length, plus one second above 40 mph
   • C.Two seconds behind the vehicle ahead, regardless of vehicle length or weight
   • D.Three seconds behind the vehicle ahead, plus additional time for weather conditions

   Answer: B. The manual says to leave at least one second for each 10 feet of vehicle length at speeds below 40 mph, and to add one more second at speeds above 40 mph.

2. 2. When should you reduce your speed below the posted limit?

   • A.Only when driving through construction zones
   • B.Only when your vehicle is heavily loaded
   • C.Only when visibility is poor due to weather
   • D.When road, weather, or traffic conditions require it

   Answer: D. You should reduce speed below posted limits whenever road conditions, weather, traffic, or visibility make it unsafe to maintain the posted speed.

3. 3. What should you do to maintain proper space cushion around your vehicle?

   • A.Manage space in front, behind, and to both sides
   • B.Focus primarily on rear space management
   • C.Maintain space only on the right side
   • D.Only worry about the space in front of your vehicle

   Answer: A. Safe space management requires maintaining adequate space cushions in all directions - front, rear, and both sides of your vehicle.

4. 4. How often should you check your mirrors while driving?

   • A.Only when changing lanes or turning
   • B.Once every minute or so, mainly on the open highway
   • C.Every 5 to 8 seconds during city driving
   • D.Only when backing up or parking

   Answer: C. You should check your mirrors every 5 to 8 seconds to stay aware of traffic conditions and potential hazards around your vehicle.

5. 5. What is the most effective way to communicate your intentions to other drivers?

   • A.Use your horn to signal lane changes
   • B.Make sudden movements to show urgency
   • C.Use turn signals well in advance of your maneuver
   • D.Flash your headlights to get attention before you move

   Answer: C. Using turn signals well in advance gives other drivers adequate time to see your intentions and react safely.

6. 6. When driving on a curve, what should you do with your speed?

   • A.Reduce speed before entering the curve
   • B.Only slow down if the curve is very sharp
   • C.Maintain the same speed as on straight roads
   • D.Accelerate slightly through the curve

   Answer: A. You should slow down before entering a curve, as centrifugal force can cause loss of control if speed is too high.

7. 7. What is a major cause of rear-end collisions involving commercial vehicles?

   • A.Mechanical brake failure in the truck
   • B.Poor road surface conditions only
   • C.Other drivers changing lanes suddenly
   • D.Following too closely behind other vehicles

   Answer: D. Following too closely is the leading cause of rear-end collisions because it doesn't allow sufficient time and distance to stop safely.

8. 8. What should you do when you feel drowsy while driving?

   • A.Drive faster to reach your destination sooner
   • B.Pull over in a safe place and rest
   • C.Open the windows and turn up the radio
   • D.Drink coffee and continue driving

   Answer: B. The only safe response to drowsiness is to pull over in a safe location and get adequate rest before continuing.

9. 9. How should you scan for hazards while driving?

   • A.Watch only the traffic signals, signs and the lane markings ahead
   • B.Look far ahead, then closer, then check mirrors regularly
   • C.Focus only on the vehicle directly in front of you
   • D.Look only at the road surface for obstacles

   Answer: B. Effective hazard scanning involves looking far ahead first, then progressively closer, while regularly checking mirrors to maintain 360-degree awareness.

10. 10. What happens to stopping distance when you double your speed?

    • A.Stopping distance increases by 50 percent
    • B.Stopping distance triples
    • C.Stopping distance doubles
    • D.Stopping distance increases four times

    Answer: D. When speed doubles, stopping distance increases by four times due to the physics of kinetic energy and braking force.