CDL psi questions

The spring brakes used on the chambers in a straight truck will bring you to a stop when air pressure drops below ___ psi.

• 20

• 60

• 100

The safety valve is set automatically when pressure is:

• 150

• 50

• 100

If your truck has a properly functioning dual air brake system and mimium size air tanks, the air pressure should build up from 85 to 100 psi within how many seconds?

• 45

• 30

• 60

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

• 2

• 3

• 1

The air compressor stops pumping air at what psi?

• 150

• 125

• 100

The driver must be able to see a low air pressure warning which comes on before pressure in the servbice air tanks fall below ___ psi.

• 80

• 60

• 40

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

• 3 psi in one minute

• 2 psi in 45 seconds

• 1 psi in 30 seconds

The driver must be able to see a low air pressure warning which comes on before pressure in the service air tanks fall below ___ psi.

• 50

• 60

• 80

An air brake system is fully charged at what psi?

• 100

• 125

• 75

The safety valve discharges automatically at the pressure of:

• 150 psi

• 50 psi

• 100 psi