#1. How can the trailer hand valve be used?
The trailer hand valve (also known as a spike, a trolley valve or a Johnson bar) controls only the trailer service brakes, not the tractor service brakes. After you have coupled your tractor to a trailer, you can use the hand valve to test the trailer service brakes independently of the tractor service brakes.
#2. f you are carrying a six-metre load weighing 8,000 kg, and each tiedown has a safe working load limit of 3,000 kg, how many tiedowns should you use?
As a rough guide, use two tiedowns for the first 3.04 metres of a load and one tiedown for every 3.04 metres after that. So for a six-metre load, use three tiedowns. In this case, the load weighs 8,000 kg, and each of the three tiedowns has a safe working load limit of 3,000 kg, which is more than adequate for the weight of this load.
#3. Which of the following statements about a converter dolly are true?
A rear semitrailer can be coupled to a converter dolly because, like the rear of a typical tractor, it has a fifth wheel and one or two axles. The hitch of the converter dolly is connected to the semitrailer in front.
#4. Unless your vehicle has antilock brakes (ABS), using light brake pressure on an icy road will
If you don’t have ABS and you brake hard on an icy road, the force of your brakes will overcome the low traction with the road surface. This will cause the wheels to lock up, possibly resulting in a skid. Instead, use extremely light pressure on the brake to control your vehicle’s speed and help prevent the wheels from locking up. If your vehicle has ABS, feel free to brake hard if necessary. The ABS computer will keep your wheels from locking up.
#5. What is a “glad hand”?
Because tractors and trailers need to be disconnected and reconnected from time to time, the air lines are equipped with quick coupling devices called glad hands. Each coupler resembles a human hand about to make a handshake.
#6. To stop quickly in an emergency, what should you do if your vehicle has antilock brakes (ABS)?
If you must stop in an emergency, apply firm, hard continuous pressure to the brake pedal until you come to a complete stop. Don’t worry about possibly locking the wheels. If the ABS computer senses that a wheel is about to lock, it will automatically release that brake to get the wheel rolling again, then reapply the brake. When ABS is working, some pulsation of the brake pedal is normal.
#7. How should you drive through a large amount of water on the roadway?
If you must drive through water, slow down and place a slight drag (that is, apply a slight constant pressure) on the brakes while you drive through the water. The slight drag placed on the brakes will reduce the amount of water and other contaminants that enter the brake drums and shoes.
#8. Reducing a tire’s air pressure when it is hot
When tires get hot, the air pressure increases. However, relieving that extra pressure may leave the air pressure too low when the tires cool again, and then the tires may catch fire or blow out. If your tires are too hot to touch, stop until they have cooled down.
#9. Idling for longer than five minutes can
Idling can burn up to four litres of fuel per hour. Idling for longer than five minutes wastes fuel, increases emissions, and can clog fuel injectors.
#10. When parking a vehicle with a two-speed axle, in which range should you leave the axle?
If your vehicle is so equipped, a two-speed drive axle allows you to select a lower gearing for greater torque at lower speeds. When you park your vehicle, you want maximum torque from both the transmission and the two-speed drive axle to prevent your vehicle from rolling, should its brakes fail. Place the transmission in the lowest forward gear, if parked facing uphill, or reverse gear (which is also a low gear) if parked facing downhill, or park if the vehicle has an automatic transmission. If the vehicle has main and auxiliary transmissions, place both in gear. If the vehicle is equipped with a two-speed axle, the axle should be in low range.
#11. Where would an air dryer be installed in an air brake system?
An air dryer may be installed in the compressor discharge line between the compressor and the first reservoir. Its purpose is to remove water vapour and contaminants from compressor air before the air enters the first reservoir. The first reservoir has usually been the supply or “wet” reservoir, so called because moisture accumulated in that reservoir before the air flowed from there to the service reservoirs. However, today’s air dryer technology is so effective that a “wet” reservoir may not be needed anymore. In a modern Air Dryer Integrated System (ADIS), the air compressor governor and the air dryer are combined into a single unit. Air from the air dryer goes directly into the primary and secondary service (“dry”) reservoirs.
#12. Which of the following types of commercial vehicles are required to carry fire extinguishers?
The following types of vehicles are required to carry one fire extinguisher: (a) school buses, (b) public passenger vehicles, and (c) limited passenger vehicles that have an authorized seating capacity of more than 10. Vehicles transporting explosives are required to carry two fire extinguishers.
#13. If you place a very heavy load on one side of a vehicle, what may happen?
If you place a very heavy load on one side of a vehicle, the brakes may lock the wheels on the underloaded side, which might cause the tires to skid on wet surfaces. It may also cause flat spots on the tires. Furthermore, the vehicle’s centre of gravity (i.e., the midpoint of its weight) will shift toward the side with the load, increasing the risk of a rollover
#14. Which of the following are normal responses from an antilock braking system (ABS)?
To perform emergency braking with ABS, just apply firm, hard, continuous pressure to the brake pedal until the vehicle stops. Don’t be concerned about brake noise, pedal movement or shudder. All this is normal with ABS. Keep applying firm pressure.
#15. Peak torque is
According to the British Columbia Driving Commercial Vehicles Manual, torque is the ability of the engine to move the vehicle, and horsepower is used to develop speed. At any given speed, the engine develops both torque and horsepower. Peak torque is found at a lower engine speed than peak horsepower. The vehicle should be operated between the engine’s peak torque and peak horsepower. This range is referred to as the normal operating rpm range of the engine.
#16. Without an oversize load permit, the tallest your vehicle can be is
The maximum allowable height for a commercial vehicle is 4.15 metres unless the driver has an oversize load permit.
#17. Under British Columbia law, what is the definition of a “special vehicle”?
Under British Columbia law, a “special vehicle” is defined as a motor vehicle that has a carrying capacity of no more than 10 persons (including the driver) and is designed or modified for public transportation of persons with disabilities.
#18. What is a commercial vehicle’s danger zone?
The section of road a vehicle travels through before it can stop is called the vehicle’s danger zone because it’s physically impossible for you to stop in time to avoid a collision with any object or person. Reduce your danger zone by slowing down and covering the brake pedal with your foot if you spot a hazard.
#19. What is brake lag time?
When you press the brake pedal, some type of force must be transmitted to the brakes to make them work. Hydraulic brake systems use brake fluid. Because brake fluid cannot be readily compressed, force is transmitted immediately to each brake when you press the brake pedal. Air brake systems use compressed air to produce the force that applies the brakes at each wheel. When you press the brake pedal, compressed air must flow from one part of the system to another. Unlike brake fluid, air is compressible, resulting in a delay of up to 0.4 seconds from the moment you apply or release the brake pedal to the moment that the brakes respond accordingly.
#20. What is the best way to dry out your brakes after you’ve driven through water?
If you’ve just driven through water, slow down and downshift into a low gear. Gently press on the brakes and maintain pressure for a short distance when you are out of the water. This will heat up the brakes and dry them out. (However, don’t overdo it, or the brakes may overheat.) Then apply the brakes to make a test stop when it is safe to do so.
#21. If your brakes get wet, what should you do?
During extremely wet conditions, or after driving through water, test your brakes by applying slight pressure with your foot to the brake pedal. Keep this pressure on for a short distance. The resulting heat will dry out the brakes.
#22. Why must you prevent tiedowns from rubbing against your load?
Tiedowns can become abraded or frayed by rubbing against the cargo. Eventually the tiedown may tear open. To prevent this, use dunnage to separate the cargo from its tiedown
#23. What is the purpose of checking your vehicle’s slack adjusters?
It’s critical that you inspect your brakes as part of the pre-trip inspection. Brakes that are out of adjustment may fail to stop your vehicle safely, possibly resulting in a dangerous collision. Federal and provincial laws require you to check manual and automatic slack adjusters daily, during the pre-trip inspection. You may be fined as much as $2,000 for driving a vehicle with defective brakes. This includes excessive brake chamber pushrod stroke
#24. When transporting a large boulder on a flatbed vehicle, you should support it with at least ____ piece(s) of hardwood blocking and secure it with at least ____ chain(s).
According to the National Safety Code Standard 10 (Cargo Securement), each large boulder must be supported on at least two pieces of hardwood blocking that extend the full width of the boulder. Each cubic-shaped boulder must be secured with two or more chains placed transversely across the vehicle and as close as possible to the hardwood blocking. Each non-cubic-shaped boulder must be secured with two or more chains forming an “X” pattern over the boulder and passing over the centre of the boulder.
#25. What does an ABS system do?
