1. What is the minimum tread depth required for front tires on a commercial motor vehicle?
- A. 2/32 of an inch
- B. 4/32 of an inch ✓
- C. 6/32 of an inch
- D. 8/32 of an inch
The FMCSA requires a minimum tread depth of 4/32 of an inch on steering (front) axle tires. Other tires require at least 2/32 of an inch. Front tires are held to a higher standard because they directly affect steering control.
2. When inspecting your vehicle before a trip, which of the following should you check for in the engine compartment?
- A. Tire pressure and lug nut torque
- B. Engine oil level, coolant level, and power steering fluid ✓
- C. Brake adjustment and slack adjuster play
- D. Fifth wheel height and kingpin condition
During the engine compartment portion of the pre-trip inspection, drivers must check fluid levels including engine oil, coolant, and power steering fluid, as well as belts, hoses, and other components. Tire and brake checks occur at different steps of the seven-step inspection.
3. How far ahead should a commercial driver generally look while driving on a highway?
- A. 3 to 4 seconds ahead
- B. 5 to 6 seconds ahead
- C. 12 to 15 seconds ahead ✓
- D. 20 to 25 seconds ahead
The FMCSA recommends that commercial drivers look 12 to 15 seconds ahead on the highway, which equates to roughly a quarter mile at highway speeds. This gives the driver time to identify hazards and react safely given the longer stopping distances of large vehicles.
4. A driver who needs to leave the road in an emergency should FIRST try to:
- A. Brake hard and steer toward the shoulder simultaneously
- B. Stay on the road and steer around the obstacle at full speed
- C. Avoid braking and steer onto the shoulder, then brake after all wheels are off the pavement ✓
- D. Downshift rapidly to use engine braking before steering
If you must leave the road in an emergency, avoid braking while steering off because braking during a sharp evasive turn can cause loss of control. If possible, keep one set of wheels on the pavement to help maintain control, stay on the shoulder, and brake gently only after the vehicle has slowed and is under control.
5. According to federal hours-of-service rules for property-carrying drivers, what is the maximum number of hours you may drive after 10 consecutive hours off duty?
- A. 8 hours
- B. 10 hours
- C. 11 hours ✓
- D. 14 hours
Property-carrying drivers may drive up to 11 hours after 10 consecutive hours off duty, subject to the 14-hour driving window. Ordinary off-duty time does not extend the 14-hour window, but qualifying split sleeper-berth periods can affect how that window is calculated under federal hours-of-service rules.
6. Which of the following statements about backing a large commercial vehicle is TRUE?
- A. You should back as quickly as possible to reduce time in a dangerous position
- B. You should always use a spotter and, if one is unavailable, get out and walk the path
- C. Mirrors eliminate the need to get out and check clearances before backing
- D. You should turn the steering wheel in the opposite direction you want the trailer to go ✓
The CDL manual teaches that when backing a trailer, you initially turn the steering wheel in the opposite direction from the way you want the trailer to go, then follow the trailer as it begins to turn. Drivers should use a helper whenever possible and get out to inspect when needed, but the manual does not state that a spotter is always mandatory.
7. What does 'gross vehicle weight rating' (GVWR) refer to?
- A. The actual weight of the vehicle including all cargo at a given moment
- B. The maximum weight specified by the manufacturer for a single vehicle including its load ✓
- C. The combined weight of the tractor, trailer, and cargo at a weigh station
- D. The weight of the vehicle when it is completely empty
GVWR is the maximum weight value specified by the manufacturer for a single vehicle, including its own weight plus the maximum load it is designed to carry. It is a rated limit, not the actual weight at any given time.
8. Under federal regulations, a CDL is required to operate a vehicle that:
- A. Has a GVWR of 20,001 lb or more
- B. Has a GVWR of 26,001 lb or more, or is designed to transport 16 or more passengers including the driver ✓
- C. Is used for interstate commerce and weighs more than 10,001 lb
- D. Has more than two axles regardless of weight
Federal law requires a CDL when the vehicle has a GVWR (or GCWR) of 26,001 lb or more, is designed to transport 16 or more passengers (including the driver), or is used to transport hazardous materials requiring placards. The 20,001 lb threshold does not trigger a CDL requirement.
9. When driving through a curve, which of the following is the BEST practice for a commercial driver?
- A. Brake firmly while in the curve to maintain control
- B. Accelerate through the curve to maintain stability
- C. Slow to a safe speed before entering the curve, then accelerate gently through it ✓
- D. Shift to a lower gear in the middle of the curve to increase engine braking
Braking or shifting in a curve can cause skidding or loss of control because the vehicle's weight shifts unpredictably. Drivers should reduce speed before entering the curve and then gently accelerate through it to help stabilize the vehicle.
10. What is the primary purpose of the 'controlled braking' technique?
- A. To bring a vehicle to a stop as quickly as possible by applying maximum brake pressure
- B. To apply the brakes hard enough to be just short of wheel lockup, maintaining steering control ✓
- C. To pump the brakes rapidly in a set rhythm to prevent skidding
- D. To use only the trailer brakes to slow the vehicle and protect the steering axle
Controlled braking means applying brake pressure as hard as possible without locking the wheels. Locked wheels cause skidding and loss of steering ability. This technique maximizes braking force while preserving the driver's ability to steer around obstacles.