Review Questions - Click On The Picture To Begin...
These Questions Are From The Illinois CDL Manual
- Stay on the shoulder until your vehicle has come to a complete stop
- Brake as hard as you can to stop as quickly as possible
- Keep one set of wheels on the pavement if possible
- Avoid braking until your speed has dropped to about 20mph
Quote From Page 42 Of The CDL Manual:
Leaving the road: In some emergencies, you may have to drive off the road. It may be less risky than facing a collision with another vehicle. Most shoulders are strong enough to support the weight of a large vehicle and, therefore, offer an available escape route. Following are guidelines if you must leave the road:
- Avoid braking - If possible, avoid using the brakes until your speed has dropped to about 20 mph. Then brake very gently to avoid skidding on a loose surface.
- Keep one set of wheels on pavement if possible - This helps to maintain control of the vehicle.
- Stay on the shoulder - If the shoulder is clear, stay on it until your vehicle has come to a complete stop. Signal and check your mirrors before pulling back onto the road.
- Around 75 psi
- Around 100 psi
- Around 125 psi
- Around 150 psi
Quote From Page 62 Of The CDL Manual:
When air tank pressure rises to the "cut-out" level (around 125 pounds per square inch, or "psi"), the governor stops the compressor from pumping air.
Be sure to understand that the air compressor governor has one main purpose and that is to tell the air compressor when to pump air and when to stop pumping air. The air compressor governor will tell the air compressor to start supplying air (cut in) and when to stop supplying air (cut out).
- Cut in air pressure is usually when air pressure falls to about 100 psi.
- Cut out air pressure is usually when air pressure raises to about 125 psi
- Straight up and down.
- It doesn't matter.
Quote From Page 7 Of The CDL Manual:
Requirements for securing the pipe
Secure each pipe with tiedowns through the pipe.
Run at least one tiedown through each pipe in the front half of the load. This includes the middle one if there are an odd number. The tiedown must run rearward at an angle not more than 45° with the horizontal when viewed from the side of the vehicle, whenever practicable.
Run at least one tiedown through each pipe in the rear half of the load. The tiedown must run forward at an angle not more than 45° with the horizontal when viewed from the side of the vehicle, whenever practicable. This holds each pipe firmly in contact with adjacent pipe.
- Using a combination of the emergency air line and the service air line
- Using the service air line
- Using the trailer tank line
- Using the emergency air line
Quote From Page 74 Of The CDL Manual:
Each trailer and converter dolly has one or more air tanks. They are filled by the emergency (supply) line from the tractor. They provide the air pressure used to operate trailer brakes.
The service air line is only used to control the service brakes (when you press on the brake pedal or use the trailer hand-valve). All other trailer air functions use the emergency line.
- Driving in poor weather conditions
- Unique roadway conditions such as driving on gravel or sand
- All of these are situations where legal maximum weights may not be safe
- Driving through mountains
Quote From Page 52 Of The CDL Manual:
During bad weather, in mountains, or unique roadway conditions such as driving on gravel or sand may not be safe to operate at legal maximum weights. Take this into account before driving.
- 25 to 75 feet
- 15 to 50 feet
- 50 to 100 feet
- 10 to 20 feet
Quote From Page 102 Of The CDL Manual:
Stop before a railroad crossing if your vehicle:
- Is placarded; or
- Carries any amount of chlorine; or
- Has cargo tanks, whether loaded or empty, used for hazardous materials. You must stop 15 to 50 feet before the nearest rail. Proceed only when you are sure no train is coming. Do not shift gears while crossing the tracks.
If there is a sign on the railroad crossing that says "exempt" or "abandoned" you do not need to stop but should still slow down and cross with caution.
- Once you are in the traffic lane and up to highway speeds
- After you have re-entered the traffic lane
- For approximately 30 seconds after re-entering traffic flow
- Before rolling forward to re-enter the traffic flow
Quote From Page 129 Of The CDL Manual:
When instructed to resume:
- Check traffic and mirrors thoroughly in all directions.
- Turn off the four-way flashers.
- Activate the left turn signal.
- When traffic permits, release the parking brake and pull straight ahead.
- Do not turn the wheel before your vehicle moves.
- Check traffic from all directions, especially to the left.
- Steer and accelerate smoothly into the proper lane when safe to do so.
- Once your vehicle is back into the flow of traffic, cancel the left turn signal.
Before you begin moving forward, you should activate the left turn signal so other motorists know you're getting ready to re-enter the traffic lane.
- Less than 2 psi in 1 minute
- Less than 3 psi in 1 minute
- Less than 1 psi in 1 minute
- There should be no loss of any psi in 1 minute
Quote From Page 66 Of The CDL Manual:
Test air leakage rate: With a fully-charged air system (typically 125 psi), turn off the engine, release the service brake, and time the air pressure drop. The loss rate should be less than 2 psi in 1 minute for single vehicles and less than 3 psi in 1 minute for combination vehicles. Then apply 90 psi or more with the brake pedal. After the initial pressure drop, if the air pressure falls more than 3 psi in 1 minute for single vehicles and more than 4 psi for combination vehicles, the air loss rate is too much. Check for air leaks, and repair before driving the vehicle. Otherwise, you could lose your brakes while driving.
You really need to memorize the allowable air leakage rates. This will very likely come up on your written exam and will come up again during the pre-trip exam. Here's what you should memorize (create flash cards if you have to).
With the service brakes released (not depressing the brake pedal):
- Air loss rate should be less than 2 psi in 1 minute for a single vehicle.
- Air loss rate should be less than 3 psi in 1 minute for combination vehicles (vehicles with a trailer).
With the service brakes depressed (pressing the brake pedal):
- Air loss rate should be less than 3 psi in 1 minute for a single vehicle.
- Air loss rate should be less than 4 psi in 1 minute for combination vehicles (vehicles with a trailer).
Be sure to have that memorized. Very important!!
- Controls the emergency brakes
- Supplies air to the trailer air tanks
- Carries air controlled by the foot brake or the trailer hand brake
- Controls the parking brakes
Quote From Page 73 Of The CDL Manual:
The service line (also called the "control line" or "signal line") carries air controlled by the foot brake or the trailer hand brake. Depending on how hard you press the foot brake or hand valve, the pressure in the service line will similarly change. The service line is connected to relay valves. These valves allow the trailer brakes to be applied more quickly than would otherwise be possible.
- 37,000 pounds
- 30,000 pounds
- 34,000 pounds
- 27,000 pounds
Quote From Page 0 Of The CDL Manual:
- 20,000 pounds single axle weight
- 34,000 pounds tandem axle weight
- 80,000 pounds gross vehicle weight
- Bridge Formula Calculations