- No more than 3 lbs in one minute
- It should not be a concern
- No more than 2 pounds in one minute
- No more than 4 pounds in one minute
From The CDL Manual
System Leak Check:
Shut off the engine, chock your wheels, (if necessary), release the tractor protection valve and parking brake (push in), fully apply the foot brake and hold it for one minute.
Check the air gauge to see if the air pressure drops more than 3 pounds in one minute (single vehicle) or 4 pounds in one minute (combination vehicle). After checking the brake with brake applied, release the foot brake and watch the gauges with brake unapplied for one minute.
Check to see if the air pressure drops more than 2 pounds in one minute (single vehicle) or 3 pounds in one minute (combination vehicle).
- To zero
- More than 20 psi
- Below 20 psi
- Below 60 psi
From The CDL Manual
Emergency System Check/Fan Down:
Turn electrical power on and begin fanning off the air pressure by rapidly applying and releasing the foot brake. Low air warning devices (buzzer, light, other) should activate before air pressure drops below 60 psi.
Continue to fan off the air pressure. Normally within the range of 20-40 psi on a tractor-trailer combination vehicle, the tractor protection valve and parking brake valve should close (pop out). On other combination vehicle types and single vehicle types, the parking brake valve should close (pop out).
- You should leave the truck
- The truck must be serviced
- The parking brake should engage
- Low air warnings should come on
From The CDL Manual
Emergency System Check/Fan Down:
Turn electrical power on and begin fanning off the air pressure by rapidly applying and releasing the foot brake. Low air warning devices (buzzer, light, other) should activate before air pressure drops below 60 psi.
Continue to fan off the air pressure. Normally within the range of 20-40 psi on a tractor-trailer combination vehicle, the tractor protection valve and parking brake valve should close (pop out). On other combination vehicle types and single vehicle types, the parking brake valve should close (pop out).
- Pull forward at 15 mph, and pump the pedal furiously
- Pull forward at 5 mph, and apply the brakes
- Pull forward quickly, and push down hard on the pedal
- Let the truck roll down a steep incline, and gently apply the brakes
From The CDL Manual
Service Brake Check:
You will be required to check the application of air or hydraulic service brakes. This procedure is designed to determine that the brakes are working correctly and that the vehicle does not pull to one side or the other.
Pull forward at 5 mph, apply the service brake and stop. Check to see that the vehicle does not pull to either side and that it stops when brake is applied.
- Leaks or damaged hoses
- Secure mounting
- You should be looking for all of these things
- Missing bolts or nuts
From The CDL Manual
Steering Box/Hoses:
Check that the steering box is securely mounted and not leaking. Look for any missing nuts, bolts and cotter keys.
Check for power steering fluid leaks or damage to power steering hoses.
- Shock absorbers
- Springs
- Suspension mounts
- All of these things must be thoroughly inspected for any kind of wear or damage
From The CDL Manual
Suspension —
Springs/Air/Torque:
- Look for missing, shifted, cracked or broken leaf springs.
- Look for broken or distorted coil springs.
- If vehicle is equipped with torsion bars, torque arms or other types of suspension components, check that they are not damaged and are mounted securely.
- Air ride suspension should be checked for damage and leaks.
Mounts:
Look for cracked or broken spring hangers, missing or damaged bushings and broken, loose or missing bolts, u-bolts or other axle mounting parts. (The mounts should be checked at each point where they are secured to the vehicle frame and axle(s)).
Shock Absorbers:
See that shock absorbers are secure and that there are no leaks.
- There should be no cracks, dents, or holes
- They should be free of contaminates
- Brake linings should be very thin
- Brake linings should not be worn thin
From The CDL Manual
Drum Brake:
- Check for cracks, dents or holes. Also check for loose or missing bolts.
- Check for contaminates such debris or oil/grease.
- Brake linings (where visible) should not be worn dangerously thin.
- Are acceptable if there are 2 or less repairs
- Are prohibited
- Require a special permit
- Are acceptable for use
From The CDL Manual
Wheels —
Rims:
Check for damaged or bent rims. Rims cannot have welding repairs.
- 2/32-inch
- 4/32-inch
- 1/32-inch
- 1/8-inch
From The CDL Manual
Tires:
The following items must be inspected on every tire:
- Tread depth: Check for minimum tread depth (4/32 on steering axle tires and 2/32 on all other tires).
- Tire condition: Check that tread is evenly worn and look for cuts or other damage to tread or sidewalls. Also, make sure that valve caps and stems are not missing, broken or damaged.
- Tire inflation: Check for proper inflation by using a tire gauge or a mallet. Note: You will not get credit if you simply kick the tires to check for proper inflation.
- That there is no mismatch tires (size and construction).
- Re-grooved or re-capped tires not permitted on bus steer tires.
- Rear tires
- All tires
- Steer tires
- Trailer tires
From The CDL Manual
Tires:
The following items must be inspected on every tire:
- Tread depth: Check for minimum tread depth (4/32 on steering axle tires and 2/32 on all other tires).
- Tire condition: Check that tread is evenly worn and look for cuts or other damage to tread or sidewalls. Also, make sure that valve caps and stems are not missing, broken or damaged.
- Tire inflation: Check for proper inflation by using a tire gauge or a mallet. Note: You will not get credit if you simply kick the tires to check for proper inflation.
- That there is no mismatch tires (size and construction).
- Re-grooved or re-capped tires not permitted on bus steer tires.