How much stopping forces is required to stop a vehicle - answer9 times the acceleration
force (4,000 hp)
What makes a truck stop slower - answerEach brake needs to take 1/16 of the braking
force (16 brakes, 8 axles if any aren't correctly adjusted if axles are not equally loaded
(other brakes would have to work harder which would create more heat, which can
cause brake damage and possible failure)
When will you vehicle begin to slow - answer3/4 of a second after you see-think, 3/4 of.
a second when you do (react)
How much distance should cars/light trucks have between them and the cars in front of
them - answer2 seconds
How much distance should busses and trucks have between them and the car in front
of them - answerNo less than 5 seconds
Brake fade - answerLoss of brake effectiveness due to overheating, brakes can catch
on fire
How much heat can brakes handle - answerUp to 250 celsius
Retarders - answerProvide an auxiliary slowing effect and assist the main brake system
to slow the vehicle - help save the main braking system from emergency stopping
What are retarders more efficient at? - answerA higher engine r.p.m and a lower vehicle
speed, so it's important to select the right gear -if slippery, can cause truck to jackknife
r.p.m - answerRevolutions per minute - refers to number of complete turns the
crankshaft makes in one minute - indicated by tachometer
How to ensure a controlled, smooth stop every time - answerTravel at a speed that
allows you to see a safe distance ahead, maintain a safe following time or distance, use
good braking skills
How to avoid wheels locking up on icy roads - answerUse extremely light pressure on
the brake to control your vehicle's speed - reduce speed when driving with tire chains
What are the most common causes of brake failure and downhill runaway crashes -
answerOverdriving the ability of the brakes to deal with the heat (poor speed control)
, What should you never do on a downgrade - answerShift to a higher gear (unless the
speed on the grade can be controlled with a retarding device or engine compression
What do signs with a percentage and a truck going downhill mean - answerShows the
steepness of the grade - the higher the percentage, the steeper the hill (18% is very
steep)
When are engine retarders most effective - answerAt a higher r.p.m and when
transmission is in a low gear
How to control speed if you are going too fast - answerApply the brakes enough to
reduce speed by 10 to 15 km/h (the brakes are cold at this point), downshift to a lower
main gear
How to drive through water when necessary - answerCover the brake pedal with your
foot as you approach the water, place a slight drag which will reduce amount of water
entering brake drums and shoes
What can happen when cargo area is empty and there's no ABS - answerThe vehicle
wheels may bounce and lock up
What can happen when you apply brake pressure too forcefully or only to the trailer
brakes on a slippery road - answerWheels can lock up which can result in a skid or
jackknife
What does ABS help prevent - answerHelps prevent wheel lockup or skids caused by
over braking on slippery road surfaces - doesn't allow you to drive faster or stop sooner.
Also prevents jackknifing
Emergency stopping with ABS - answerFirm, continuous pressure to the brake pedal
until vehicle is stopped, don't pump brakes (turns vehicle on and off), don't be alarmed
by noise
Automatic Traction Control (ATC) - answerOptional addition to an ABS system, uses the
pulsating signal from the speed sensors to detect loss of drive wheel traction on slippery
road surfaces - will apply the brakes (has info decal on dashboard and dash mounted
lamp that will light if wheel spin occurs)
What percent of greenhouse gas emissions are produced by the road transportation
sector - answer27 percent
When should you increase following distance - answerWhen road conditions are less
than ideal
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