Radial and bias-ply tires should not be used together. All wheels on a vehicle should be the same style and equally-sized.

While inspecting a coupling, you should go under the trailer and look into the back of the fifth wheel. Ensure that the fifth wheel jaws are secured around the shank of the kingpin.

A vehicle inspection report keeps the carrier informed about any problems that need to be fixed.

During the vehicle inspection test, you will be asked to do a complete inspection of your vehicle. You will need to explain what you are inspecting and why.

Older trailers do not have spring brakes. This means that if the air supply in an older trailer's air tank has leaked away, there will be no working brakes connected to the trailer and its wheels will turn freely.

One way to know when it is time to shift gears is to learn your vehicle's operating rpm range. You should shift up when your engine reaches the top of that range. You can also learn which speeds each gear is good for and shift up based on your speedometer.

Explosives are placed in hazardous materials Class 1.

The most important reason to inspect your vehicle is to ensure the safety of yourself and other road users.

Potential warning signs of fatigue include difficulty focusing, frequent blinking, or heavy eyelids; yawning repeatedly or rubbing your eyes; daydreaming; wandering or disconnected thoughts; trouble remembering the last few miles you've driven; missing exits or traffic signs; having trouble keeping your head up; drifting from your lane; following too closely; hitting a shoulder rumble strip; or feeling restless and irritable.

Both systems in a dual air brake systems share a single air compressor. If the air compressor is damaged, neither system will be able to operate properly.

If the coolant temperature gauge goes above the highest safe temperature, you should stop driving as soon as possible and try to figure out what is wrong. There could be an issue in your vehicle that could lead to engine failure and possibly a fire.

During the vehicle inspection test, you will be required to do a complete inspection of your vehicle. During this inspection, you must explain to the examiner what you are inspecting and why you are inspecting those items.

When planning to turn left at an intersection, make sure you have reached the center of the intersection before beginning the turn. If you turn too soon, off-tracking may cause the left side of your vehicle to hit another vehicle.

In a vehicle with dual parking control valves, there is a separate air tank that can be used to temporarily release the spring brakes if they have been activated due to low air pressure. Pushing in the proper control will release the spring brakes for a short period of time, allowing the driver to move the vehicle in an emergency.

Aggressive driving is defined as operating a motor vehicle in a selfish, bold, or pushy manner. Road rage is defined as operating a motor vehicle with the intent of doing harm to others, or the intent of physically assaulting another driver or their vehicle.

To ensure that you can see as well as possible, don't wear sunglasses when driving at night. If you wear eyeglasses, make sure they are clean and unscratched. Make sure you are rested and alert before driving at night.

Doubles and triples take up more space than other commercial vehicles. Before entering or crossing traffic while driving a double or triple, be sure there is a space large enough for your entire vehicle to operate without causing any collisions.

Regrooved, recapped, or retreaded tires are not permitted to be used on the front of a bus.

A steering wheel should be held firmly with each hand on opposite sides of the wheel.

Be sure to check your mirrors before beginning a drive. Your posture may change day to day and your mirrors may need to be adjusted.