Arizona CDL Knowledge Test Class B: Practice Test

Before a trip, you should check each slack adjuster after parking, setting wheel chocks, and disengaging the parking brake. Pull the slack adjusters to make sure that they do not move more than about one inch from where the push rod is attached. If they move more than one inch, they may be out of adjustment and will need to be fixed.

Speeding is the leading cause of death and injury in work zones. Use extra caution when driving near workers in a work zone.

All commercial motor vehicles are required to be equipped with the proper emergency equipment. This may include spare electrical fuses; three red reflective triangles, six fuses, or three liquid burning flares; and at least one properly charged and rated fire extinguisher. Optional equipment includes tire chains, tire changing equipment, a list of emergency phone numbers, and an accident reporting kit/packet.

To avoid overusing your brakes, you should always shift into a lower gear before starting down a hill.

Drivers of vehicles equipped with ABS and drivers of vehicles without ABS should brake in relatively the same manner. When ABS is working properly, it automatically applies when brakes are applied in situations that may create lockup.

If you are not certain that your vehicle will fit under overhead objects, you should slow down and take a different route, if possible.

On a slippery road, you must adjust your driving speed to fit conditions. Because it will take longer for your vehicle to stop on a slippery road than on a dry road, you should increase your following distance when conditions are slippery. Avoid driving in a way that requires you to change speeds frequently.

In an air brake system, air tank drains are used to remove water and compressor oil from the air tanks. When operating a drain, be sure to drain the tank completely.

Cargo and its securement must be inspected every time you take a break during a trip. Be sure to inspect the cargo at least every 150 miles.