Rust around wheel nuts may mean that they are loose. Check the tightness of the nuts if you see any rust in the area.

In bad weather, many automobile drivers will follow large trucks too closely, particularly if visibility is poor.

You will not be able to brake or steer your vehicle without adequate traction. Ensure that your tires are in proper working condition before beginning a trip.

Tractor protection controls in older vehicles may be operated by levers instead of knobs. If an air supply control is set in its "normal" position, it is properly set for you to pull a trailer.

You should always slow to a safe speed before entering a curve. Slowing while within the curve could cause a skid.

When driving, you should frequently check the mirrors on both sides of your vehicle.

The body removes alcohol at a fixed rate. The more alcohol consumed, the longer it will take for the body to remove the alcohol from its system.

When performing a visual check of coupling devices, you should make sure there is no space between the upper and lower fifth wheel. Ensure that the locking jaws are securely closed around the kingpin.

If your brakes are hot after coming down a steep grade, you should not use your parking brake when parking. Let your brakes cool before applying the parking brake or risk damaging the brakes.

Many large CMVs are equipped with air brakes. An air braking system uses compressed air to operate.

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.

The air compressor of an air brake system is connected to the engine through gears or a v-belt. The compressor may be air-cooled or cooled by the engine cooling system.

Most newer heavy-duty vehicles use dual air brake systems. A dual air brake system has two separate air brake systems which use a single set of brake controls.

When examining the engine compartment during a pre-trip inspection, you should check the engine oil level, the radiator coolant level, and the condition of the hoses.

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.

A properly adjusted mirror will show some portion of the vehicle. This will provide a point of reference to help the driver judge the distance of other objects to the vehicle.

Stopping is not always the best way to avoid a hazard. If there is not enough space for you to stop to avoid coming into contact with the hazard, swerving out of the way may be your safest option.

To prevent a vehicle with manual transmission from rolling backward when you begin to move forward from a stopped position, you can partly engage the clutch before removing your foot from the brake pedal.

Air brakes function through the use of compressed air.

Backing is always dangerous and should be avoided whenever possible. When parking, look to park in a space that will allow you to pull forward when exiting.