Convex mirrors are also known as "fisheye", "spot", or "bug-eye" mirrors.

When inspecting your tires, verify that there is tread depth of at least 4/32 of an inch in every major groove on the front tires and tread depth of at least 2/32 of an inch in grooves on the other tires. Be sure that your tires are not too worn, are not cracked, have proper air pressure, and are all equally sized.

Large combination vehicles take longer to stop when they are empty than when they are loaded. The decreased weight causes a vehicle's wheels to have decreased traction on the surface of the road.

It is important to always perform a thorough pre-trip inspection before beginning a drive. When inspecting the upper fifth wheel, the glide plate should be securely mounted to the trailer frame.

Stay aware of upcoming obstacles and hazards by consistently watching the road at least 12 to 15 seconds ahead of your vehicle. When traveling at highway speeds, this is equivalent to about a quarter of a mile.

Accelerate smoothly and gradually. Rough acceleration can cause mechanical damage.

Driving while fatigued is dangerous and increases the risk of a crash. Take precautions before a trip to prevent driving while fatigued.

To test hydraulic brakes, you should pump the brake pedal three times, then apply firm pressure to the brake pedal and hold for five seconds. The pedal should not move. If it does, there may be a leak.

To test the trailer service brakes, you should first ensure that the braking system has a normal air pressure level, then release the parking brake. You should then move the vehicle forward slowly and apply the brakes with the hand control. If the trailer service brakes are working properly, you will feel the brakes activate.

If your trailer goes off course while you are backing, you should pull your truck forward and reposition your vehicle as needed before continuing to back up.

Always apply the parking brake when leaving your vehicle.

The easiest way to become aware that your trailer has begun to skid is to observe it in your mirrors. Checking your trailer in your mirrors will also allow you to spot any skidding at the earliest possible moment.

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

To maintain proper control of your vehicle, the steering wheel should be held firmly with both hands. Your hands should be positioned on opposite sides of the wheel.

All trucks, truck tractors, and buses must be equipped with emergency brakes and parking brakes. These brakes must be held by mechanical force.

Be sure to test the trailer emergency brakes before beginning a trip. After ensuring that the trailer rolls freely, you can test the emergency brakes by pulling out the trailer air supply control, or placing it in the "emergency" position. Pull forward slightly with the tractor and make sure the trailer does not move.

Drum brakes are attached to the wheels and located on the axles of a vehicle. The braking mechanisms that cause the vehicle to stop can be found inside of a drum brake.

The emergency air line (also known as the supply line) has two functions. The first is to supply air to the trailer air tanks on a combination vehicle, and the second is to control the emergency brakes.

Spring brakes come on automatically when air pressure drops to an unsafe psi level. Instead of waiting for the spring brakes to automatically activate, you should safely exit the road as soon as you notice the low pressure warning signal and bring your vehicle to a stop while you are still able to control the brakes.

When driving, you should scan the road at least 12 to 15 seconds ahead of your vehicle. This will allow you to notice hazards as early as possible, giving you time to react to them appropriately.