clp study Flashcards
what is the most important reason for doing a vehicle inspection?
Safety
What things get checked during a trip?
instruments, air/temp/pressure gauges, ammeter/voltmeter, mirrors, tires, cargo, lights
Name some key steering parts
wheel, tie rod, shaft, gear box, pitman arm, drag link, knuckle, spindle.
cracked or broken spring hangers are a defect of the _______ system?
suspension
what three kinds of emergency equipment MUST you have?
spare fuses, three red reflective triangles, fire extinguisher
what is the minimum tread depth on front tires?
4/32
what is the minimum tread depth on rear tires?
2/32
air pressure should build from 50 to 90 with in how many minutes?
3
what should wheel bearing seals be checked for?
leaks
steering wheel play must not exceed ______ degrees?
10
what two types of tires CANNOT be used in conjunction?
Radial and bias-ply
the trailer brake valve or (Johnson bar) activates the brakes on the trailer and NOT the tractor. True or false?
true. it only applies the service brakes to the trailer gradually
cargo must be inspected within the first 50 miles and every ______miles or ____hrs, whichever comes first.
150 miles, 3hrs
how do you test hydraulic brakes for leaks?
pump brake pedal 3 times
apply pressure and hold for 5 seconds
pedal should not move
you should avoid _______whenever you can.
backing
if you must back what two things can make it as safe as possible?
back to the drivers side, use a helper
how do you start moving when parked on a hill, without moving backward?
partially engage the clutch before taking right foot off brake
what is the most important hand signal you and a helper can agree on?
stop
two special conditions where you should downshift are?
before going down a hill
before entering a curve.
when should you downshift automatic transmissions?
when going down grades
retarders keep you from skidding when the road is slippery. true or false?
false
when should you turn off retarders?
when drive wheels have poor traction.
what are the two ways to know when to shift?
engine speed, road speed
how long do you have to put out warning devices if stopped on a shoulder?
ten minutes.
what are two main things to look for ahead?
vehicles entering the highway, your lane, turning.
brake lights
in safe driving, communicating also means?
signaling intentions.
where should you place reflectors when stopped on a divided highway?
10, 100, 200 feet behind you for approaching traffic
what three things add up to total stopping distance?
perception, reaction, & braking distance
if you go twice as fast your stopping distance increases by 2 or 4 times?
4
empty trucks brake better than loaded trucks. true or false?
false
reduce speed to _____ on wet roads and _____ on packed ice.
1/3 & 1/2 or more
how can you regain control when hydroplaning?
release the accelerator and press the clutch
what is the safest speed to drive in heavy traffic?
The speed of other vehicles (the flow of traffic)
hydroplaning is more likely when the tire pressure is _____?
Low
you should shift to a lower gear before or after starting a long down grade?
Before
how do you find how many seconds of following distance you have?
wait until the car ahead of you passes a landmark and count the seconds until you reach it.
if you are driving a 30 ft vehicle at 55 mph, how many seconds of following distance should you allow?
4
why is it unwise to swing left before turning to the right?
another vehicle may try to pass on the right and get pinched
what is a hazard?
a possible danger
a red triangle with an orange center is the symbol for?
slow moving vehicle
when should you eliminate all in-vehicle distractions?
before driving begins
________ driving is operating a motor vehicle in a selfish, bold, or pushy manner.
aggressive
what four things can you do when dealing with aggressive drivers?
avoid eye contact
ignore gestures
report to authorities
call police
in hot weather, check tire pressure about ever ____ hrs or ____miles.
2, 100
drivers of modern trucks should go down in a _____ gear than they came up in
Lower
when going down long steep grades you should brake _____mph below your safe speed then let off the brake.
5
how long does it take a typical tractor -trailer to cross a double track?
15 seconds
vehicle s required to stop at cross-buck signs must stop no closer than 15 and no more than _____ feet from tracks.
50
low boys, car carriers, moving vans, possum belly, livestock trailers, single axle tractor pulling long trailers with landing gear for a tandem axle trailer all have one thing in common in a certain driving situation. What is it?
They get stuck on raised railroad crossings.
what is brake fade?
more power must be applied to brakes to get the same stopping power due to overheating
stopping is not always the best option in an emergency. true or false?
true
when executing a quick turn you should never ?
apply the brake
if a tire blows out you must remember to stay______?
off the brakes and hold the wheel firmly
when returning to the road in lieu of stopping, you must hold the wheel tightly and ________, do not _________ on the road
turn sharply, edge back gradually
two ways to stop quickly and safely are to use ?
controlled braking and stab braking
the type of braking that occurs when you lock up the wheel then re-apply when they roll free again is called?
stab braking
what are two reasons hydraulic brakes fail?
loss of hydraulic pressure and fade
skids caused by ______________ happen most in ice and snow
Acceleration
to regain traction in slippery conditions?
push the clutch in
what are the four ways to cause a skid?
over braking
over steering
over acceleration
driving to fast
to correct a drive wheel braking skid?
stop braking
counter steer
the 3 basic steps to be taken at any accident are
protect the area
notify authorities
care for the injured
what two things cause tire fires?
over inflation and duals that touch each other
the first step in fighting a fire in a tractor is?
get the vehicle off the road and stop
when fighting an engine fire, dont ______?
open the hood
BAC at ____ is the legal limit for a holder of a CDL
.04%
placcards on hazardous material vehicles must be read from _____ sides and be at least ______ inches
4, 9.84
you cannot inspect sealed loads but you can check that you don’t exceed?
gross weight and axle weight limits
who is responsible for an overloaded vehicle?
the driver
cargo straps are required every ___ feet and any load regardless of size must have no less than ___?
10, 2
federal regulations require that aggregate working load limit of any securement system be at least _______ times the weight of the article or group of articles
1 1/2
dry bulk tanks require special care because they have a
high center of gravity
what is a supply air pressure qauge used for?
shows tank pressure
what are spring brakes?
emergency brakes with powerful springs that are held back by air pressure. if air pressure is removed or lost, they engage
front wheel brakes are good under all conditions. true or false?
True
spring brakes come on at a pressure range of ____to _____ psi?
20 to 45
a visible warning signal for low air pressure must come on at ____ psi or half the cutout pressure for older models?
60
wig-wags drop at a psi of______?
55
on large buses, the low pressure warning device activates at _____to_____psi?
80-85
never ____________ when the spring brakes are on?
push the brake pedal down.
what should you do if you are driving and the low pressure warning device or buzzer sounds at 55-60 psi?
stop and safely park the vehicle
before driving a vehicle with a dual air system, what should you let the system pressure build to?
100 psi
slack adjusters in s cam type brakes, should not move more than ______ when you pull on it.
1 inch
brake drums and disks must not have cracks longer than _______the width of the friction area?
1/2
air pressure should build from 80-100 psi in _____seconds when the engine is running at normal operating speed?
45
when conducting the air leakdown test, and while holding the foot pedal for 1 minute, the pressure should not drop more than____psi for single and _____psi for combination vehicles?
3&4
the tractor protection valve comes on at _____to______psi and engages the __________?
20-45, spring brakes
fanning on and off the brake pedal will _______air pressure, this is how you check that the __________ ___________ come on automatically.
reduce, spring brakes
the use of brakes on long steep grades is only a supplement to the?
braking effect of the engine.
why do air brakes take a half second or so longer to reach the braking mechanism as opposed to hydraulic brakes?
it takes air longer to flow through the lines.
when should you drain air tanks without automatic drain valves?
at the end of each driving day
you will not have normal braking functions if ABS quits working. true or false?
false. you still have normal braking functions
what two things are important to prevent rollover?
keep cargo as close to the ground as possible
drive slowly around turns
when you turn suddenly while pulling doubles, which trailer is more likely to turn over?
the rear, last one
why should you not use the trailer hand brake to straighten out a jackknifing trailer?
the brakes caused the skid in the first place and it will not work
when rear wheel follow a different path than the front wheels in a turn, it is referred to as ________?
off tracking
when backing a trailer, you turn the wheel the _______direction you want the trailer to go? and then you ______to follow
opposite, turn the other way
the service line is also called a _____ line and is ______
control, blue
the emergency line is also called the _______line and is _____?
supply, red
glad hands connect at a __________ angle?
90 degree
why should you not use the trailer hand valve (Jonson bar) while driving?
it can cause a skid, and should only be used for parking
the trailer air supply control on newer vehicles is ________ and you ____to supply with air and _____to set the emergency (spring brakes).
red handle that looks like a stop sign, push, pull
what is the service line for?
carries air when the foot pedal or trailer hand brake is applied.
what is the emergency line for?
supplies air to the tanks, controls the emergency brake on combination vehicles.
shut off valves are used at the ______ of trailers used to tow other trailers. when pulling more than one trailer, all the shut off vales must be ______except for the last one.
back, open
what might happen if the trailer is too high when you try to couple?
it may not couple correctly
how much space should you have between the apron and the fifth wheel plate?
none
to drive, you only need to raise the landing gear enough to lift off the pavement. true or false?
false, you must raise it all the way up
re-grooved tires cannot be used where?
front wheels of busses
mud flaps must be at least ____ inches off the ground.
10
