126 terms


CDL general knowledge for CDL written test
If you have an air brake restriction...
you may not operate a CMV
What is the most important reason for doing a vehicle inspection?
Safety. Safety for yourself and other road user.
What things should you check during a trip?
Watch gauges for signs of trouble.

Use your senses to check for problems (look,listen,smell,and feel)

Check critical items when you stop : tires, wheels, rims, brakes, lights, reflectors, electrical connections to trailers.
Name some key steering wheel parts
Gear box

pitman arm

steering knuckle

steering arm

tie rod
Name some suspinsion system defects
Broken leaf spring, spring hangers that allow movement of axle.

U-bolts, or other axle poistioning parts that are cracked, or damaged.
What 3 kinds of emergency equiptment must you have?
Spare electrical fuses

Three red reflective triangles

properly charged and rated fire extinguisher.
What is the minimum tread depth for front tires? For all other tires?
4/32 on the front and 2/32 elsewhere
Name some things you should check on the front of your vehicle during the walk around inspection?
Headlights, low and high beam.

Windshield wiper arms for proper spring tension.

Wiper blades for damage.


Turn Signals both left and right.
What should wheel bearing seals be checked for?
Leaks, Leaks, LEAKS!!
How many red reflective triangles should you carry?
How do you test hydraulic breaks for leaks?
Pump brake pedal three times and apply firm pressure to the pedal, hold for five seconds. The pedal should not move.
Why put the starter switch key in your pocket during the pre-trip inspection?
To keep someone from running over you.
Why should you back toward the driver's side?
So you can see better

backing toward the right side is very dangerous because you cant see as well.
If stopped on a hill, how can you start moving without rolling back?
For manual transmission, partly engage the clutch before you take your right foot off the brake, or put the parking brake on whenever necessary to keep you from rolling back.

On a tractor-trailer equipped with a trailer brake hand valve, the hand valve can be applied to keep from rolling back.
When stopping a vehicle with a manual transmission, push the clutch in when the engine is close to
When backing, why is it important to use a helper?
There are blind spots you cant see!
What is the most important single you and your helper should agree on?
stop, stop, stop!!
What are the two special conditions where you should downshift?
Before entering a curve

Before starting down a hill
When should you down shift automatic transmissions?
You can select a low range to get greater engine braking when going down grades

The lower ranges prevent the transmission from shifting up beyond the selected gears ( unless the governor rpm is exceeded )

Engine retarders keep you from skidding when the road is slippery
What are the two ways to know when to shift?
Use engine speed (rpm) or road speed (mph)

All drivers look ahead, but many don't look far enough ahead
How far ahead does the manual say you should look ahead?
Most good drivers look at least 12 to 15 seconds ahead
What are some things to look for ahead?
Look for vehicles coming onto the highway, into your lane, or turning.

Watch for brake lights from slowing vehicles

by seeing these things far enough ahead, you can change your speed, if necessary.
Whats the most important way to see the sides and rear of your vehicles?
By using your mirrors you can see?
Tires and cargos

Loose straps, ropes, or chains

Mirrors can only be checked accurately when the trailer is straight.

There are blind spots that your mirrors cannot show you?
Some drivers try to help out others by signaling when it is safe to pass. Should you do this?
No, don't do it. You can be blamed if an accident occurs!
What does "communicating" mean in safe driving?
Other drivers can't know what you are going to do until you tell them.

You communicate your intentions by using turn signals for turns and lane changes
When you pull off the road and stop, be sure to...
Turn on the four-way emergency flashers
How should you put out the triangles?
Hold them between yourself and the on-coming traffic for your own safety
If you stop on a 2-lane road carrying traffic in both directions, place warning devices within...
10 feet of the front or rear corners to mark location of vehicle and 100 feet behind and ahead of the vehicle.
It takes longer to stop on slippery surfaces, so you should....
Reduce speed by 1/3 on a wet road and 1/2 on packed snow

If the surface is icy, reduce speed to a crawl and stop driving as soon as you can safely do so.
Where should your reflectors be placed when stopped on a divided highway?
Place warning devices 10 feet, 100 feet, and 200 feet in the rear toward the approaching traffic
What three things add up to total stopping distance?
Preception Distance + Reaction Distance + Braking Distance = Total STopping Distance
If you go twice as fast, your stopping distance will increase by..
Four times as much

Empty trucks have the best braking
What is hydroplaning?
The tires loose their contact with the road and have little or no traction
Hydroplaning can occur at speeds as low as ___ mph if their is a lot of water.
What is "Black Ice?"
A thin layer that is clear enough that you can see the road underneath it

It makes the road look wet

Any time the temp is below freezing and the road looks wet, watch out for black ice!

You should alwasy be able to stop within the distance you can see ahead.
At night, you can't see as far with low beams, so you should..
Slow down

In heavy traffic, the safest speed is that of other vehicles as long as it is legal and not excessive for conditions.
When driving through a roadway work zone, you should
Decrease your speed for adverse weather or road conditions.

Decrease your speed even further when a worker is close to the roadway.

If the vehicle ahead of you is smaller than yours, it can probably stop faster than you can.
How do you find out how many seconds of follwoing distance space you have?
Wait until the vehicle ahead passes a pavement marking, or some other clear landmark. Count off the seconds.

Compare your count with the rule of one second for every ten feet of length.
If you are driving a 40-foot vehicle at 35 mph, how many seconds of following distance should you allow?
Four seconds
If you are driving a 60-foot vehicle at 55 mph, how many seconds of following distance should you allow?
Seven seconds
Why should you avoid traveling next to other vehicles?
Another driver may change lanes suddenly and turn into you

You may be trapped when you need to change lanes
Why are strong winds a problem?
They make it difficult to stay in your lane and it is even worse for lighter vehicles.

You should decrease your following distance if somebody is follwoing you too closely.
Many drivers forget about the space under their vehicles which can cause them to..
Get hung up

If you swing wide to the left before turning right, another driver may try and pass you on the right.

Before you start across a road, make sure you can get all the way across before traffic reaches you.
What is a hazard?
A hazard is any road condition or other road user ( driver, bicyclist, pedestrian ) that is a possible danger.
Why should you make emergency plans when you see a hazard?
Being prepared will reduce the danger!
How can you recognize distracted drivers?
Vehicles that drift over the lane divider lines, or travel at inconsistant speeds.
What are some tips to follow so you wont become a distracted driver?
Review and be totally familiar with all safety and usage features on any in-vehicle electronics, including your wireless phone, before you drive.

Pre-program radio stations and pre-load all cd's and cassets.
What is the definition of agressive driving and road rage?
Agressive driving is the act of operating a motor vehicle in a selfish, bold, or pushy manner, w/o regard for the rights or safety of others. An agressive driver may change lanes abruptly and without warning.

Road rage is operating a vehicle with the intent of doing harm to others or physically assaulting a driver or their vehicle.
What should you do when confronted with an agressive driver?
Make every attempt to get out of their way. Do not challenge them by speeding up.

Avoid eye contact, and ignore gestures and refuse to react with them.
What are some things you can do to reduce your stress before and while you drive?
Listen to "easy listening" music

Give the drive your full attention. Don't allow yourself to become distracted by talking on you cell phone, eating, etc.
During night driving with low beams you can see about ___ feet ahead.

During night driving with high beams you can see about ___ feet ahead.


Dirty headlights may give only 90 % of the light they should?
You should avoid driving through deep puddles or flowing water if possible. If you can't, you should...
Gently put on brakes, this presses lining against brake drums.

Increase engine RPM and cross water while keeping light pressure on breaks.
At railroad crossings your speed must be...
reduced in accordance with your ability to see approaching trains in any direction.

held to a point which will permit you to stop short of the tracks if a stop is necessary.

At a railroad crossing you should skip shift quickly on the tracks to get off them.

It is illegal to shift gears while crossing railroad tracks.

If your brakes fade, set the parking brake to stop the vehicle.

You should use low beams whenever you can.
The best advice for driving in fog is...
During winter driving you should pay extra attention to the following...
Tire chains

Defrosting and heating equiptment.
What effects can wet brakes cause? How can you avoid these problems?
Can cause loss of braking power, wheel lockups, pulling to one side or the other.

Water in the brakes can cause the brakes to be weak, to apply unevenly, or to grab.

You should let air out of the hot tires so the pressure goes back to normal.
In hot weather, inspect tires every...
Every 2 hours or 100 miles
When can you safely remove the radiator cap?
When system has cooled.
What factors determine your selection of a "safe" speed when going down a long, steep downgrade.
Total weight of the vehicle and cargo.

Legnth of grade, steepness of grade, road conditions, and weather.
Why should you be in proper gear before starting down a hill?
You may not be able to shft into lower gears.

You may not even be able to get back into any gear and all engine braking affect will be lost.
Descibe the proper braking technique when going down a long, steep downgrade.
Apply the brakes just hard enough to feel a definate slow down. When your speed has been reduced to approximately 5 mph BELOW your "safe" speed, release the brakes. (this brake application should last for about 3 seconds)

When your speed has increased to your "safe" speed, repeate previous step.
Railroad crossings with steep approaches can cause...
Your unit to hang up on the tracks.

Modern trucks may have to use lower gears going down a hill than would be required to go up the hill.

Brakes kept in good condition rarely fail.
If you loose your brakes on a downgrade, you should....
Use the escape ramp
What type of vehicles can get stuck or railroad-highway crossing?
Low slung units ( lowboy, car carrier, moving van, possum-belly livestock trailer )

Single-axle tractor pulling a long trailer with its landing gear set to accommodate a tandem-axle tractor.
How long does it take a typical tractor-trailer unit to clear a double track?
At least 14 seconds to clear a single track and more than 15 seconds to clear a double track.
Why is stopping not always the safest thing to do in an emergency?
You can almost alwasy turn to miss an obstacle more quickly than you can stop.

When you don't have enough room to stop, you may have to steer away from whats ahead.
What are some advantages of going right, instead of left around an obstacle?
If an oncoming driver has drifted into your lane, a move to your right is best.

If that driver has realized what has happened, a natural reaction is to move back into their lane.
What is an "escape ramp?"
A bed of loose, soft material to slow a runaway vehicle.

Escape ramps are sometimes used in combination with an upgrade.

If a tire blows out, you shoould put the brakes on hard and stop quickly.
The major signs of tire failure are...
Sound. The loud "bang" is an easily recognized sign.

Vibration. The vehicle thumps or vibrates heavily.

When leaving the roadway in an emergency, avoid using the brakes until your speed has dropped to 20 mph. Once dropped to 20 mph, brake gently. If possible, keep one set of wheels on the roadway.

When leaving the roadway in an emergency, brake as hard as you can and get back on the roadway as soon as possible.

Controlled braking is when you apply your brakes all the way, and release the brakes when the wheels lock up.
With stab braking you apply the brakes as hard as you can without locking up the brakes.
How do you know if your vehicle has antilock brakes.
Tractors, trucks, and busses will have yellow ABS malfuntion lamps on the instrument panel.

Trailers will have yellow ABS malfunction lamps on the left side, either on the front or rear corner.
What is the proper braking technique when driving a vehicle with antilock brakes.
Use only the braking force necessary to stop safely and stay in control.

Brake the smae regardless or wether you have ABS.
How do antilock brakes help you?
ABS helps you avoid wheel lock up and loss of control.
What advantages do you have with ABS?
Brake pressure is adjusted to provide the maximum braking without the danger of lockup.

If you ABS malfunctions, you still have regular brakes.

The most common skid is where the rear wheels loose traction through excessive braking or acceleration.

Driving to fast for conditions causes most front-wheel skid.

The frist thing to do at a crash scene is to keep another crash from happening in the smae spot.

It takes time, not coffee or a cold shower to sober up.
What are some things to do at an accident scene to prevent another accident?
If you are involved in the crash, try and get to the side of the road.

If you are stopping to help, park away from the crash.
Name two causes of fire tires.
Under-inflated tires

Duals that tocuh.

The B:C type fire extinguisher is designed to work on electrical fires and burning liquids.

When using a fire extinguisher, you should get as close as possible to the fire.
Name some causes of vehicle fires.
Under-inflated tires and duals that touch.

Electrical system. Short circuts due to damaged insulation and loose conncetions.

Common over the counter medicines for colds can make you drowsy.
What is a hazardous material placard?
a sign placed on the outside of a vehicle to identify the type of hazardous cargo.

You can drive a vehicle that carries hazardous materials if it does not require placards.

Never drive a a vehicle requiring a hazardous material placard unless you have a hazardous material endorsement.
You must keep your hazmat shipping papers...
On the drivers seat whe out of the vehicle.

In a pouch on the driver's door, or in clear view within reach while driving.
What is "sleep debt"
If you don't sleep enough, you "owe" more sleep to yourself.

You can't overcome it with will power and it won't go away on its own.
What are some things related to cargo that drivers are responsible for?
Inspecting your cargo, recognizing overloads and poorly balanced weight.

Knowing your cargo is properly secured and does not obsrtuct your view ahead or to the sides.
How often must you stop while on the road to check your cargo?
After you have driven 3 hours or 150 miles and recheck on each of your brakes.
After starting on your trip, when should you check your securing devices?
Within the first 50 miles of starting your trip.
When should your highbeams be dimmed for oncoming traffic and when following other vehciles?
Within 500 feet for oncoming traffic and 350 feet when following another vehicle.
Name two situations where legal maximum weights may not be safe.
Mountain driving

During bad weather.
What can happen when you don't have enough weight on the front axles?
Under-loaded front axles ( caused by shifting weight too far to the rear ) can make the steering axle weight too light to steer safely.
What is the minimum number of tie-downs for any flat bed load?
At least 1 tie down for every 10 feet of cargo.

No matter how small the cargo, it should have at least 2 tie-downs.
Name two basic reasons for covering cargo on an open bed.
To protect ther people from spilled cargo.

To protect the cargo from bad weather.
What must you check before trasporting a sealed load.
You cant inspect a sealed load, but you should check that you don't exceed gross weight and axle weight limits.
Special care should be taken with loads that have a high center of gravity: examples include..
Dry bulk tanks

Hanging meat

Blocking is used in the front, back, and/or sides of a piece of cargo to keep it from sliding.