CDL Quiz
Questions: 16 · 10 minutes
1. During a wheel inspection, you notice rust trails extending from several lug nuts. What can this indicate?
The tire contains too much air pressure
The brake drum has recently overheated
The lug nuts may be loose
The wheel bearing has been over-lubricated
2. Your brakes are fading on a steep downgrade, and an escape ramp is available ahead. What is the best choice?
Use the escape ramp rather than risk losing control farther downhill
Shift into neutral so the vehicle can reach the ramp faster
Continue to the bottom while pumping the brakes rapidly
Stop in the travel lane before reaching the ramp
3. Your vehicle begins to hydroplane on a rain-covered road. What is the best immediate response?
Ease off the accelerator and avoid hard braking or abrupt steering
Turn sharply toward the shoulder to leave the standing water
Increase speed slightly to push through the water
Apply the parking brake gradually to restore tire contact
4. You smell smoke and discover a fire in the tractor’s engine compartment. Which response is most appropriate after stopping safely?
Leave the engine running so the cooling fan disperses the heat
Fully open the hood immediately to locate the base of the fire
Shut off the engine, avoid fully opening the hood, and use the proper extinguisher if it is safe to do so
Pour water into the engine compartment regardless of the fire source
5. Your commercial vehicle stalls on a railroad crossing and a train may be approaching. What should you do?
Remain in the cab and repeatedly try to restart the engine
Walk along the track toward the train and signal the engineer
Release the brakes and attempt to push the vehicle off the tracks alone
Get out, move well away from the tracks, and call 911 and the posted railroad emergency number
6. Two trailers carry the same total weight, but one has much more weight stacked high above the floor. How does the higher load affect handling?
It improves traction without changing rollover tendency
It raises the center of gravity and increases rollover risk in turns
It shortens stopping distance because weight transfers downward
It reduces off-tracking because the trailer leans into curves
7. During a pre-trip inspection, you find that the steering wheel has substantially more play than the vehicle manufacturer allows. What should you do?
Proceed if the tires appear properly inflated
Drive at reduced speed and check it again at the next stop
Have the steering defect assessed and corrected before operating the vehicle
Compensate by holding the steering wheel more firmly
8. You must back a tractor-trailer into a space with a choice of approaches. Which approach is generally preferred?
Back toward the passenger side because the mirror is farther from the trailer
Begin from either side and rely primarily on the rear convex mirror
Use the approach requiring the longest reverse path to allow gradual corrections
Back toward the driver’s side so you can see the trailer path more clearly
9. Before beginning a long, steep downgrade, when should you select an appropriate low gear?
After the vehicle starts gaining speed
Before starting down the grade
Halfway down, after evaluating the grade
When the service brakes first begin to fade
10. You are driving a 60-foot commercial vehicle at 45 mph in good conditions. Using the common CDL following-distance guideline, how much space should you allow?
About 6 seconds
About 4 seconds
About 8 seconds
About 7 seconds
11. You approach an overpass and are uncertain whether your commercial vehicle has enough clearance. What should you do?
Follow the route if a consumer GPS directs you beneath the overpass
Stop before the overpass and verify the clearance or use a confirmed safe route
Assume the posted clearance includes extra space for commercial vehicles
Drive under slowly while watching the top of the trailer in the mirrors
12. What is the main safety benefit of an antilock braking system, or ABS, on a commercial vehicle?
It always shortens stopping distance on every road surface
It helps prevent wheel lockup and maintain steering control during hard braking
It automatically applies the parking brakes if traction is lost
It removes the need to adjust speed for wet or icy roads
13. A front tire suddenly blows out while you are traveling at highway speed. What should you do first?
Brake firmly before the vehicle begins to drift
Steer immediately onto the shoulder while maintaining speed
Grip the wheel firmly, stay off the brake initially, and let the vehicle slow under control
Accelerate until the steering becomes lighter, then change lanes
14. A commercial vehicle becomes disabled on the shoulder of a straight, two-way undivided road. What is the standard warning-device arrangement?
Place one near the vehicle and one about 100 feet in each direction
Place all three devices 100 feet behind the vehicle
Place one 50 feet behind, one 100 feet behind, and one 200 feet behind
Place one beside each rear tire and one on the cab roof
15. Which cargo-inspection schedule best matches the standard rule for a trip when cargo securement is the driver's responsibility?
Inspect within the first 50 miles, then after duty-status changes and every 3 hours or 150 miles, whichever comes first
Inspect only before departure and at the final destination
Inspect after the first 100 miles, then once every 6 hours
Inspect at fuel stops only, unless the load feels unstable
16. A loaded truck is approaching a sharp curve. Which technique best helps prevent a skid or rollover?
Maintain speed until entering the curve, then brake firmly
Coast through the curve in neutral to avoid sudden acceleration
Brake lightly throughout the curve while steering toward the outside edge
Slow to a safe speed before the curve, then apply gentle power through it