Class E - Georgia

The control handle on the dashboard that may be used to apply spring brakes gradually is called the what?

Modulating Valve

Some vehicles have a separate air tank can be used to release what?

The spring brake

You need at least what tread depth in the front tires and what tread depth in other tires?

4/32inch in front
2/32inch in back

Steering wheel play of what degree can make it hard to steer.

10 degrees or two inches

If more than one-forth or more leaf springs are leaking then what will happen?

It will put the vehicle out of service

What warning devices are needed for parked vehicles?

Three reflective warning triangles, or 6 fuses, or 3 liquid burning flares

How much should pressure build in 3 minutes? Also governor cutout.

Pressure should build from 50 psi to 90 psi in 3 minutes. Governed cut out at 120-140 psi

What safety equipment is needed?

Spare electrical fuses unless vehicle has circuit breakers and three red reflective triangles or three red burning flares

What does oil pressure need to be?

5-20 psi

Operating 35-75 psi

How to test for hydraulic leaks

Pump the break pedal three times then apply firm pressure and hold for 5 seconds the pedal should not move if it does something is wrong

When should drivers inspect trucks and cargo?

They must inspect the securement of cargo within the first 50 miles of a trip and every 150 miles or three hours, whichever comes first

Road speed is measured in what unit?

Mph

Engine speed is measured in what unit?

Rpm

Retarders do what?

Help slow a vehicle

Four basic types of retarders

Exhaust,engine, hydraulic, and electric

When should you turn the retarder off?

When drive wheels have poor traction, turn it off in icy, snowy, or wet conditions.

How far should you look ahead?

About 12-15 seconds. At lower speeds about a block. At higher speeds about a quarter mile

When should mirror adjustment take place?

Before the start of a trip when the trailers are straight

What are curved mirrors called?

Fisheye, spot, bugeye

When should you signal turns?

Signal early, signal continuously, and make sure you turn off your turn signal after the turn

If you stop on any road you must put out your warning devices when?

Within ten minutes

Where to place warning triangles on a two way street?

100ft ahead, 10ft back, 100 ft back

Where to place warning triangles on a one way street?

10, 100, 200 ft back

From the time your eyes see a hazard until your brain reacts to it is called what? What is the average time and distance at 55 mph?

Perception distance; 1 & 3/4 seconds and 42 feet

Distance continued to travel before you physically hit the brakes is called what? What is the average time and distance at 55 mph?

Reaction distance; 3/4-1 seconds and 61 feet

Distance your vehicle will travel while braking is called what? What is the distance the vehicle will travel while braking when originally going 55 mph?

Braking distance; 216 feet

What is total stopping distance from 55 mph?

419 feet

When you double your speed from 20 to 40 mph what is the impact?

It is four times greater that the braking distance is four times longer

When you triple your speed from 20 to 60 mph what is the impact?

The impact and braking distance is 9 times longer

If speed increases to 80 mph…

Then the impact and braking distance is 16 times greater than 20 mph

Slippery surfaces

Reduce speed by 1/3 from about 55mph to 35mph on a wet road if snow by half of icy then to a crawl

Hydroplaning can occur at

Speeds as low as 30mph if a lot of water

The braking effect if greatest when

It is near the governed Rpms and the transmission is in lower gears

What is the number one cause of injury and death in roadway work zones

Speeding traffic

How many seconds do you need for each 10 feet of vehicle

1second per 10 feet unless going faster than 40 then add a second

Two dangers in traveling next to others

Another driver may change lanes and suddenly turn into you and you may be trapped when you need to switch lanes

Avoid blinding others

You should dim your lights within 500 feet of oncoming or when following another vehicle

Inspecting tires in hot weather

Inspect the tired every two hours or every 100 miles in hot weather

Passing crossing

No traffic control devices

Active crossing

Has traffic control devices

How long does it take a typical tractor trailer to cross a track?

At least 14 seconds and more than 15 for a double track

You must use the braking effect of the engine

As the principle way of controlling your speed

When going down grade you should

Shift the transmission to low gear

What is not always the safest thing to do in an emergency

Stopping

What do you not apply while turning?

Brakes

When Avoiding a crash avoid using your brakes until it is going about

20mph

Most brakes kept in good condition rarely fail. Most hydraulic brakes fail because of one of two reasons

Loss of hydraulic pressure

Brake fade on long hills

Anti lock braking system (abs)

Helps keep your vehicle under control during hard braking

A skid if cause in one of four ways

Over braking, over steering, over acceleration, and driving too fast

When a front wheel skids the only way to stop the skid is to

Let the vehicle slow down

Basic steps to take at accident

Protect area notify authorities, care for injured

You should distribute cargo

So it is as low as possible put the heaviest parts under the lowest parts

The load limit of the securing article must be

At least one half times the weight of the article

Too little weight on the driving axels can cause

Poor traction

Cargo should have at least

Two tie downs and one tied own for each ten feet of cargo

What is the cut out and cut in pressure for the Grovner of the air suppresses

125cut off 100 cut in

What is set to open if the pressure in the air tanks exceed 150?

Pressure relief valves

Foundation brakes are at each wheel what is the most common type of brake

S-cam drum brake

Low pressure alarm comes on at

Below 60 psi or one half the compressed governor cutout pressure on older vehicles

On large buses it is common for the low pressure alarm to go off at

80-85 psi

What pumps air into the storage tanks/reservoirs?

Air compressee

Compressed air usually has some water and some compressor oil in it which is bad for?

The air brake system

If more than one-forth or more spring leaf is broke

Deadline the vehicle

Tractor and straight truck spring breaks will come on fully when?

Air pressure drops to a range of 20-45psi(typically 20-30psi)

Some vechicles such as buses have a separate air tank which can be used to release the

Spring brakes

A duel air brake system has two separate air brake systems which use

A single set of brake controls

Before driving a vehicle with a duel air system, allow time for the compressor to build up

To a minimum of 100psi pressure in both primary and secondary systems

If a slack adjuster moves more than about one inch where the push rod attaches

It probably needs adjustment

When engine is at operating Rpms, the pressure should build from 85-100psi within

45 seconds in dual air systems

With a fully charged air system typically 125psi. Turn off the engine and release the parking brake and time the air pressure drop.

The loss rate should be less then two psi in one minute for single vehicles and less then three psi in one minute for combination

The following two things will help you prevent rollover

Keep cargo as close to the ground as possible and drive slowly around turns

Large combination vehicles take longer to stop when they are

Empty then when fully loaded

The earliest and best way to recognize that the trailer has started to skid Is by

Seeing It in your mirrors

When a vehicle goes around w corner the rear wheels

Follow a different path then the front wheels this is called off tracking or cheating

If you cannot complete your turn without entering another traffic lane

Turn as wide as you complete the turn

Try to back up with a trailer

In a straight line

Trailer hand valve never use hand valve for parking because

All the air might leak out unlocking brakes

What does the tractor protection valve do

Keeps air in the tractor or truck brake system should the trailer and break away or develop a bad leak

The tractor protection valve the I'll close automatically if

Air pressure is low(range of 20-45psi)

Every combination has two air lines

The service line and the emergency line

What are coupling devices used to connect the service and emergency air lines from the truck or tractor to the trailer

Glad hands