Illinois CDL Permit Test - Class B

Hydroplaning is similar to water skiing: your vehicle's tires glide along the road on a film of water without having traction with the surface of the road.

Always downshift before beginning to drive downhill. Take the hill at a speed that does not require you to overuse your brakes.

Anti-Lock Braking Systems (ABS) are compatible with air braking systems. ABS helps maintain control of a vehicle and prevents the wheels from locking up during hard braking on slippery surfaces. ABS can still provide benefits even if is present on only one axle.

Driving at night is more dangerous than driving during the day. It is more difficult for drivers to see hazards, the glare of headlights can affect drivers' vision, and there are more fatigued and impaired drivers on the road.

Air brakes are an effective and safe way of stopping large and heavy vehicles, as long as they are maintained and used properly.

If you must drive in reverse, you should back up slowly and use the mirrors on both sides of your vehicle. Use a helper to monitor your blind spots whenever possible. You and the helper should agree on a signal for "stop."

When driving down a steep grade, you should rely primarily on the braking effect of the engine to slow down. To prevent overheating, use your brakes only as a supplement to this slowing technique.