A tractor without a semi-trailer

A tractor with two semi-trailers

A tractor that goes faster than the speed limit

A tractor that goes slower than the speed limit

Are more likely to roll over than empty rigs.

Are less likely to roll over than empty rigs.

Are just as likely to roll over as empty rigs.

Massachusetts CDL Combination 1 - DMV Written Test Questions with Answers

Q.1

If a trailer begins to jackknife, you should not:

Release the brakes.
Apply the trailer hand brake.
Allow the wheels to grip the road.
Allow the trailer to straighten out.

Q.2

Simply changing lanes can cause:

A “crack-the-whip” effect, resulting in a rollover.
A trailer to straighten out.
Confusion over which lane the driver is hoping to use.
Other drivers to reduce their speed.

Q.3

How many air lines does a combination vehicle have?

One
Two
Three
Four

Q.4

A lightly-loaded combination vehicle will stop more slowly than a fully-loaded vehicle because:

The stiff suspension springs and strong brakes will have high traction.
The stiff suspension springs and strong brakes will have low traction.
The brakes only operate when a trailer reaches a minimum weight.
The suspension springs only operate when a trailer reaches a minimum weight.

Q.5

Driving a combination vehicle ____ than driving a single vehicle.

Is easier
Requires more driving skill
Is better for training
Is safer in inclement weather

Q.6

To help prevent a rollover, cargo should be:

Placed as high as possible inside the trailer.
Placed as low as possible inside the trailer.
Placed on the passenger side of the trailer.
Placed on the driver’s side of the trailer.

Q.7

Trailers with low underneath clearance may be difficult to drive:

On interstate highways.
Over railroad crossings.
On dirt roads.
At the posted speed limit.

Q.8

If a load is placed on one side of a trailer, the trailer:

May lean, and could result in a rollover.
May add extra support during turns.
Have improved braking.
Have improved steering.

Q.9

When lightly loaded, combination vehicles:

Should not be driven.
Have reduced braking capabilities.
Will not rollover.
Should be loaded with most of the weight in the rear of the trailer.

Q.10

A tractor protection valve is:

A device that keeps air in the tractor or truck brake system, should the trailer break away or develop a bad leak.
A device that prevents theft.
A device that controls fuel levels.
A device that allows the battery to recharge efficiently.

Q.11

Failure to keep the fifth wheel plate properly greased could:

Cause the trailer to disconnect.
Cause steering problems.
Cause braking problems.
Affect the lights.

Q.12

When a combination vehicle goes around a corner:

The turn should be made as tightly as possible.
The front and rear wheels move in different paths.
The rear wheels should run over the curb.
It is acceptable for street signs to be knocked over if they are too close to the road.

Q.13

What does the trailer air supply control look like?

It is a square blue knob.
It is a triangular yellow knob.
It is an eight-sided red knob.
It is a circular orange knob.

Q.14

What is a bobtail?

A tractor without a semi-trailer
A tractor with two semi-trailers
A tractor that goes faster than the speed limit
A tractor that goes slower than the speed limit

Q.15

To lower the risk of a rollover, you should:

Load the cargo as far forward as possible.
Load the cargo as far back as possible.
Load the cargo as low as possible.
Stack the cargo as high as possible.

Q.16

When the wheels of a trailer lock up:

The trailer will stay straight.
The trailer tends to swing around.
The cab will swing, but the trailer will stay straight.
They will likely go flat.

Q.17

Fully-loaded rigs:

Should not be driven.
Are less likely to roll over than empty rigs.
Are more likely to roll over than empty rigs.
Are just as likely to roll over as empty rigs.

Q.18

When backing a trailer, how should you turn the steering wheel?

Turn the top of the steering wheel in the direction you want the trailer to go.
Turn the top of the steering wheel in the direction opposite of where you want the trailer to go.
It doesn’t matter.
It depends on where the trailer is being backed.

Q.19

The emergency air line:

Is controlled by the foot brake.
Is connected to the relay valves.
Supplies air to the trailer air tanks.
Prevents skids.

Q.20

After coupling, there should be ____ between the upper and lower fifth wheel.

No space
Very little space
A lot of space
Three inches of space