CDL School

Because you cannot see everything behind your vehicle, backing is always dangerous. Avoid backing whenever you can. When you must back, here are a few simple safety rules: Start in the proper position, look at your path, use mirrors on both sides, back slowly, back and turn toward the driver's side whenever possible, and use a helper with clear hand signals whenever possible.

Air brakes are three different systems: service brake, parking brake, and emergency brake.

ABS helps you avoid wheel lock up and maintain control. You will not be able to use stab braking on a vehicle equipped with ABS.

Basic method for shifting up: release accelerator, push in clutch and shift to neutral at the same time. Release clutch. Let the engine and gears slow down to the rpm required for the next gear. Push in clutch and shift to the higher gear at the same time. Release clutch and press accelerator at the same time.

Use either the tachometer or the speedometer and upshift/downshift at the right rpm or road speed.

You should check your mirrors every 8 to 10 seconds to know what is going on around your vehicle.

You need at least 4/32-inch tread depth in every major groove on front tires. No fabric should show through the tread or sidewall. There should be no cuts or other damage.

Blocking is used in the front, back, and/or sides of a piece of cargo to keep it from sliding. Blocking is shaped to fit snugly against cargo. It is secured to the cargo deck to prevent cargo movement.

Inspect the cargo and its securing devices again within the first 50 miles after beginning a trip. You need to inspect again after you have driven for 3 hours or 150 miles and after every break you take while driving.

Empty trucks actually require greater stopping distances because an empty vehicle has less traction. It can bounce and lock up its wheels, giving much poorer braking.

The Gross Vehicle Weight Rating (GVWR) is the value specified by the manufacturer as the loaded weight of a single vehicle.

Do the following to correct a drive-wheel braking skid: stop braking letting the rear wheels roll again and keep the rear wheels from sliding; counter-steer as a vehicle turns back on course, it tends to keep on turning. Unless you turn the steering wheel quickly the other way, you may find yourself skidding in the opposite direction.

Low air warning devices (buzzer, light, flag) should activate before air pressure drops below 60 psi or level specified by the manufacturer.

The governor controls when the air compressor will pump air into the air storage tanks. When air tank pressure rises to the "cut-out" level around 125 psi, the governor stops the compressor from pumping air. When the tank pressure falls to the "cut-in" pressure around 100 psi, the governor allows the compressor to start pumping again.

Before you change lanes, you must first make sure that no vehicles are hiding in your blind spots.

Accident statistics show that the chance of a crash is much greater for drivers who have been drinking than for drivers who have not.

Before you begin backing, work out a set of hand signals that you both understand. Agree on a signal for "stop."

To test the parking brake: fasten safety belt, set parking brake, place vehicle into a low gear, and gently pull forward against parking brake to make sure the parking brake holds.

All vehicles with air brakes have a pressure gauge connected to the air tank. If the vehicle has a dual air brake system, there will be a gauge for each half of the system.

Some vehicles have sight glasses, see-through coolant overflow containers, or coolant recovery containers. These permit you to check the coolant level while the engine is hot. If the container is not part of the pressurized system, the cap can be safely removed, and coolant added even when the engine is at operating temperature.

Explanation: A skid happens whenever the tires lose their grip on the road. Most serious skids result from driving too fast for road conditions. Drivers who adjust their driving to conditions don't over-accelerate and don't have to over-brake or oversteer from too much speed. 

The B:C type fire extinguisher is designed to work on electrical fires and burning liquids. These are usually the following types of fire extinguishers: Regular Dry Chemical, KCl Dry Chemical, Carbon Dioxide (Dry), Halogenated Agent (Gas).

Commercial vehicle must be equipped with 3 red reflective triangles, 6 fuses or 3 liquid burning flares.

It will take longer to stop, and it will be harder to turn without skidding, when the road is slippery. Wet roads can double stopping distance at any speed, reduce speed, and slow down gradually on a wet road. 

Whether or not you load and secure the cargo yourself, you are responsible for inspecting your cargo, recognizing overloads and poorly balanced weight, knowing your cargo is properly secured and does not obscure your view ahead or to the sides, knowing your cargo does not restrict your access to emergency equipment.

Air pressure increases with temperature. Do not let air out or the pressure will be too low when the tires cool off.

Never leave your vehicle unattended without applying the parking brakes or chocking the wheels. Your vehicle might roll away and cause injury and damage.

Explanation: Don't roll back when you start. You may hit someone behind you. If you have a manual transmission vehicle, partly engage the clutch before you take your right foot off the brake. Put on the parking brake whenever necessary to keep it from rolling back. Release the parking brake only when you have applied enough engine power to keep from rolling back 

Slow down to a safe speed, and downshift to the right gear before entering the curve. This lets you use some power through the curve to help the vehicle be more stable while turning. It also allows you to speed up as soon as you are out of the curve.

Explanation - For an e-route inspection: check the tires, wheels, and truck body for signs of heat whenever you stop during a trip.

Without ABS you still have normal brake functions. Drive and brake as you always have.

When driving a loud bang, vibrations, or heavy steering can indicate that a tire has failed.

Remember that when the road is slippery, you need much more space to stop, and should keep more space in front of your vehicle.

Explanation: Warn following drivers by flashing your brake lights, don't stop suddenly. If you see a hazard that will require slowing down, warn the drivers behind by flashing your brake lights. At dawn, dusk, in rain, or snow, you need to make yourself easier to see so turn on your lights. 

You must review the inspection report made by the previous driver. Only if defects reported earlier have been certified as repaired or not needed to be repaired, should you sign the previous driver's report.

In a front-wheel skid, the front end tends to go in a straight line regardless of how much you turn the steering wheel. On a very slippery surface, you may not be able to steer around a curve or turn.

Poor weight balance can make vehicle handling unsafe. The cargo should be loaded so that it is balanced in the cargo area.

To know how much space you have, wait until the vehicle ahead passes a shadow on the road, a pavement marking, or some other clear landmark. Then count off the seconds like this: "one thousand-and-one, one thousand-and-two" and so on, until you reach the same spot.

Your CDL will be disqualified after two or more convictions of any state law on texting while operating a CMV. No motor carrier shall allow or require its drivers to engage in texting while driving.

Wedge brakes and disc brakes are less common than s-cam brakes.

When you're in an accident and not seriously hurt, you need to act to prevent further damage or injury. The basic steps to be taken in any accident are to: protect the area, notify authorities, and care for the injured.

With the stab braking method, you apply your brakes all the way and release brakes when wheels lock up. 

If an oncoming driver has drifted into your lane, a move to your right is best. If that driver realizes what has happened, the natural response will be to return to their own lane. No one is likely to be driving on the shoulder, but someone may be passing you on the left.

Most vehicles now have an ABS light on the instrument panel that will light up briefly when the vehicle is started to alert you that the vehicle has ABS, you can check to see if the vehicle was built on or after March 1, 1998, or you can check for wires from your brakes.

In some vehicles, a control handle on the dashboard may be used to apply the spring brakes gradually. This is called a modulating valve. It is spring loaded, so you have a feel for the braking action. The more you move the control lever, the harder the spring brakes become on. They work this way, so you can control the spring brakes if the service brakes fail.

In a front-wheel skid, the front end tends to go in a straight line regardless of how much you turn the steering wheel.

You will lose your CDL for at least one year for a first offense for: Driving a CMV if your blood alcohol concentration is .04% or higher or driving a CMV under the influence of alcohol.

You should brake in a way that will keep your vehicle in a straight line and allow you to turn if it becomes necessary. You can use the "controlled braking" method or the "stab braking" method. 

If you find yourself being tailgated: avoid quick changes, signal early, reduce speed very gradually, increase your following distance, and don't speed up.

Don't over steer, over accelerate, or over brake by adjusting to conditions while driving. These include traction, curves, visibility, traffic and hills.