Do not assume that posted height clearances are accurate. If the road was repaved after the sign was posted, or if there is packed snow on the ground, the actual height of the opening may be different than what is indicated. If you are not confident that your vehicle will be able to safely clear an upcoming bridge or overpass, you should slow down and find another path, if possible.

Any vehicle with air brakes must be equipped with a low air pressure warning signal.

In general, you should always use the parking brake when parking your vehicle. However, you should not apply the parking brake if your brakes are very hot or if your brakes are wet and temperatures are below freezing.

Hydroplaning is an effect in which a vehicle's tires lose traction with the surface of the road and instead glide along a layer of water. There does not have to be a large amount of water on the road for this to occur.

It is important to observe other drivers' actions and identify clues that a person could be driving impaired. Drivers who have had too much to drink, are sleepy, are on drugs, or are ill can present hazards to other drivers. One sign that a driver may be impaired is that they stop in inappropriate places, such as at green traffic lights.

When using a fire extinguisher, you should stand as far away from the fire as possible. Aim the extinguisher at the base of the fire, not at the flames. If you are not sure which kind of extinguisher should be used on a fire, particularly a hazardous materials fire, you should wait for the firefighters to arrive and allow them to extinguish it.

When parking on a level surface, you should use wheel chocks. If the vehicle is not equipped with spring brakes, this is essential to prevent the trailer from moving.

After a vehicle is started, the warning lights and buzzers should go out after a few seconds. If the warning signals do not turn off, there may be something wrong with the vehicle.

Railroad-highway crossings may be difficult to cross when pulling a trailer with a low underneath clearance. In particular, both low-slung units and single-axle tractors pulling long trailers are especially challenging to drive over raised crossings.

In an air brake system, the air compressor pumps air into the air storage tanks. The air compressor is controlled by the air compressor governor.

In general, a smaller vehicle will be able to come to a complete stop faster than a larger vehicle. Keep this in mind when determining your following distance.

You should stay in the right lane of a multilane road if your vehicle is being slowed down by a heavy load. Allow other vehicles to pass your truck using the left lane.

Combination vehicles require more space on the road than other vehicles. When entering or crossing traffic while driving a combination vehicle, it is especially important that there is a large enonugh gap in traffic to safely do so.

Explosives are placed in hazardous materials Class 1.

A maximum posted speed limit is the fastest a vehicle may travel under ideal circumstances. A driver should decrease their driving speed as conditions require. A driver should never exceed the legal speed limit.

When making a turn, be sure to steer gently and smoothly. Making a quick turn while pulling trailers is dangerous and can increase the risk of the last trailer rolling over.

Always turn on your four-way emergency flashers if you must park on the side of the road. This is especially important when traveling at night.

You should shift your vehicle's transmission into a low gear before staring a downhill grade. Be prepared for gravity to increase your vehicle's speed when traveling downhill.

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.

Brakes out of adjustment will fade before those that are properly adjusted. Brake adjustment must be checked frequently to help prevent brake issues.