Air Brake Practice Test

When is it ok to leave you truck unattended without applying the parking brakes?

The stop light switch:?

It is not safe to drive a vehicle that has brake drums with cracks that are longer than___the width of the friction area

To test air service brakes, you should:

A slack adjusters free play needs to be adjusted if it moves more than____ inches when you pull hard on it?

If air pressure is not built up within the proper amount of time, then:

The safety valve reduces pressure at what PSI?

Why should you drain water from compressed air tanks?

If your vehicle has an alcohol evaporator, every day during cold weather you should:

The air loss for a straight truck or bus with the engine off and the brakes on should not be more than:

The driver must be able to see a low air pressure warning which comes on before the pressure in the service air tanks fall below____PSI:

The air brake lag distance at 55 MPH on dry pavement adds about ____ feet:

If your truck has a properly functioning dual air brake system and minimum size air tanks, the air pressure should build from 85 to 100 psi in ____ seconds:

How should you check that your service brakes are working properly?

A straight truck or bus air brake system should not leak at a rate greater than ___ psi per minute with the engine off and the brakes released:

Excessive use of the service brakes results in overheating which can lead to:

The safety valve is set to automatically reduce tank pressure at what psi?s?

If you must make an emergency stop, you should brake so you:

Your truck or bus has a dual air brake system. If your low air pressure warning comes on for only one system, what should you do?

The brake pedal in an air brake system:

All air brake equipped vehicles have:

With air brake vehicles, the parking brake should be used:

A straight truck or bus air brake system should not leak at a rate of more than ___ psi per minute with the engine off and brakes released:

To check the free play of manual slack adjusters on S cam brakes, you should park on:

The use of brakes on a long and steep downgrade under normal conditions is only a supplement to:

The most important thing to do when a low air pressure warning comes on is:

The parking or emergency brake on a heavy vehicle can only be held in position by something that cannot leak away, like:

Why drain water from compressed air tanks?

Repeatedly partially releasing and pressing the brake pedal may result in:

The brake system that applies and releases the brakes when the driver uses the brake pedal is the ____ brake system:

A slack adjuster needs to be adjusted if the free play is more than ____ inches when you pull hard on it:

An air brake system is fully charged at what psi?

If the spring brakes are on, when should you push the brake pedal?

When brakes are applied, brake shoes will press against the:

Emergency stab braking is:

Modern air brake systems combine three different systems. They are the service, the parking, and the ____ brakes:

If you do not have automatic tank drains, how often should you drain the oil and water from the bottom of compressed air storage tanks?

The proper use of brakes on a long, steep grade after selecting a proper gear is to brake until your speed is about ___ mph below the posted safe speed, then release your brakes:

In ideal conditions, a truck or bus with air brakes going at 55 mph would require a stopping distance of:

The application pressure gauge shows how much air pressure you:

The spring brakes on brake chambers on a straight truck will bring you to a stop when air pressure drops below ___ psi?

Some air brake systems have an alcohol evaporator. What may happen if you don’t keep the proper level of alcohol in its container?

The braking power of the spring brakes:

Which of these is NOT a proper time to apply the parking brakes

If your truck or bus has a dual parking control valve, you can use pressure from a separate tank to:

The most common type of foundation brake found on heavy vehicles is the:

With air brake vehicles, the parking brake should be used:

Excessive heat caused by using your brakes too often can also cause:

The supply pressure gauge shows how much air pressure:

If you are going down a steep downgrade and you have reached a speed of 40 mph, you would apply the service brake until your speed has dropped to below ___ mph:

Your truck has a dual air system and one of the systems loses its pressure. What will happen?

Parking or emergency brakes on trucks and buses can legally be held on by ___ pressure:

The S-cam:

Under normal conditions, in order to engage the parking brakes, the driver:

Total stopping distance for air brakes is longer than for hydraulic brakes due to ___ distance:

During normal driving, spring brakes are usually held back by:

The air compressor stops pumping air at what psi?

The braking power of the spring brakes:

Your brakes are fading when:

If your vehicle has an alcohol evaporator, it is there to:

The air compressor governor controls:

Air braking takes more time than hydraulic braking because: