Wyoming CDL DMV Endorsement Double 1

Height warnings are often, but not always, posted on low bridges. If you are unsure if you will be able to clear an overhead object, go slowly.

Shut-off valves are used in air supply lines to control the passage of air from one trailer to another. The rear shut-off valve should always be closed to prevent air from leaving the braking system.

If you are being followed too closely, you should increase your following distance, avoid making quick moves, and avoid relying on tricks (such as flashing your lights) to help other drivers pass. Speeding up may only increase the danger by causing the tailgater to continue tailgating you at a higher speed.

Never unlock the pintle hook with the dolly still under the rear trailer. This could cause the dolly tow bar to fly up, possibly causing serious injury.

To reduce the risk of tipping over when driving with a trailer, you should steer gently and smoothly. Avoid making sudden movements.

More than half of all accident-related truck driver deaths are a result of truck rollovers. To help prevent a rollover, be sure to load cargo low to the ground and centered on your rig. Take corners slowly and carefully.

Because you can't see everything behind you, backing is always dangerous and should be avoided whenever possible. Choose parking spaces from which you can pull forward when you leave.

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.

Driving combination vehicles requires more skill than driving single commercial vehicles. Combinations are generally longer, generally heavier, and are more vulnerable to rollover.

Driving a combination vehicle usually requires more skill than driving a single vehicle. Combination vehicles are generally longer and heavier than single commercial vehicles.

Air brakes consists of three separate braking systems: the service brake system, the parking brake system, and the emergency brake system.

To check your vehicle's lights before a trip, you should set the parking brake, turn off the engine, remove the key from the ignition, and take the key with you. Turn on your low beam headlights and four-way flashers. Get out of the vehicle to make sure the lights are working properly.

Most hydraulic brake failures occur for one of two reasons. A first likely cause of brake failure is that the brakes have been overused on a downgrade, causing them to fade. The second likely cause is that there has been a loss of hydraulic pressure in the braking system. Brakes kept in good condition will rarely fail, but you should know which steps to take in case they do.

An air brake system has a safety relief valve, which releases air from the tanks if the pressure gets too high. If the valve must operate, something in the system is wrong and should be addressed by a mechanic.

If your hydraulic bakes fail, shifting into a lower gear can help slow your vehicle down.

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

A steering wheel should have no more than 10 degrees of play. This is equal to about two inches of movement at the rim of a 20-inch wheel. If there is more play than this, it may be difficult to steer.

Wheels or rims that have had welding repairs should never be used.

If a vehicle is equipped, an application pressure gauge shows how much air pressure is being applied to the brakes. This gauge can help a driver identify if their brakes are beginning to fade.

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.