Wisconsin CDL Permit Test - Knowledge Test Class A

A wig wag is a type of low air pressure warning device in an air brake system. It drops a mechanical arm into the driver's view when the air pressure in the tanks falls below 60 psi.

When transporting cargo on a flatbed trailer, you should use at least one tie-down for every 10 feet of cargo. Any cargo, no matter how small, should be restrained by a minimum of two tie-downs.

When inspecting your windshield, you should look for cracks or other problems that could interfere with your ability to clearly see the road. The windshield wiper arms should be checked for proper spring tension. The wiper blades should be checked for damage, stiff rubber, and improper securement.

If you use your brakes too much when traveling on a steep downgrade, they may overheat and become less effective. To avoid causing your brakes to overheat on a steep hill, you should rely on engine braking.

When performing a static leakage test on a triple combination vehicle with air brakes, the leakage rate should be no more than 5 psi in one minute. If air leaks from the air brake system at a quicker rate, the vehicle should not be driven because something likely needs to be repaired.

Smoking, eating, or drinking are distracting activities and should be avoided while you are driving. Instead, plan ahead and allow yourself time to stop to eat when making a lengthy trip.

Operators driving too fast is a major cause of fatal crashes. You must continually adjust your speed to a rate that is safe for road and traffic conditions.