WorksheetsCombinations Practice Test
Total questions: 20
Worksheet time: 10mins
Name
Class
Date
1.
After connecting the air lines but before backing under the trailer, you should:
a)
Release the service brakes.
b)
Use the trailer hand brake.
c)
Counter-steer.
2.
After you lock the kingpin into the fifth wheel, you should check the connection by:
a)
Pulling the tractor ahead gently with the trailer brakes locked.
b)
Pulling the tractor ahead sharply to release the trailer brakes.
c)
Pulling forward 50 feet, turning right and left.
3.
You are coupling a tractor and semitrailer and have connected the air lines. Before backing under the trailer you should:
a)
Make sure that the trailer brakes are off.
b)
Pull ahead to test the glad hand connections.
c)
Supply air to the trailer system, then pull out the air supply knob to lock the trailer brakes.
4.
In general, the higher the "center of gravity" of your truck the:
a)
More stable it is when turning.
b)
Easier it is to turn around corners.
c)
Easier it is to turn over.
5.
You will know if the trailer you are driving has antilock brakes by:
a)
Yellow ABS malfunction lamps on the right side of the trailer.
b)
Yellow ABS malfunction lamps on the left side of the trailer.
c)
Red malfunction lamps on the trailer brake cylinders.
6.
Loss of air pressure in the emergency line causes:
a)
An increase in air pressure to the service line.
b)
The trailer's emergency brakes to come on.
c)
The relay valves to close.
7.
When coupling, the proper position of the fifth wheel is:
a)
Tilted up towards the end of the tractor.
b)
Tilted down towards the end of the tractor.
c)
Level with the ground.
8.
If you must back your trailer on a curved path, you should try to position your vehicle so you can back:
a)
To the driver’s side
b)
To the passenger's side.
c)
In a straight line.
9.
To unlock the fifth wheel, pull the release handle to the ____ position.
a)
Neutral
b)
Open
c)
Closed
10.
When uncoupling a trailer, after you have shut off the trailer air supply and locked the trailer brakes, you should:
a)
Back up gently to ease pressure on the fifth wheel locking jaws.
b)
Immediately put on your tractor parking brakes.
c)
Begin to lower the trailer landing gear.
11.
After connecting the air lines but before backing under the trailer, you should:
a)
Walk around the rig to be sure that it is clear.
b)
Make sure that the trailer brakes are off.
c)
Supply air to the trailer system, then pull out the air supply knob.
12.
A trailer is most likely to jackknife when it is:
a)
Loaded to full capacity.
b)
Empty.
c)
Over loaded.
13.
Compared to a straight truck or bus, there are ___ things to inspect on a combination vehicle.
a)
The same number of
b)
Fewer
c)
More
14.
Where should the tractor be when you inspect the landing gear after uncoupling a trailer?
a)
With the fifth wheel directly beneath the kingpin.
b)
Completely clear of the trailer.
c)
With the tractor frame under the trailer.
15.
When checking that the trailer is securely coupled to the tractor, the landing gear should be:
a)
Fully lowered.
b)
Fully raised.
c)
Slightly raised.
16.
You are driving a COMBINATION vehicle when the trailer breaks away, pulling apart both air lines. You would expect the trailer brakes to come on and:
a)
The tractor protection valve to close.
b)
The trailer supply valve to stay open.
c)
The tractor to lose all air pressure.
17.
The safety catch for the fifth wheel locking lever must be ____ for a coupling to be complete.
a)
Over the locking lever
b)
Straight up
c)
Through the locking lever.
18.
To be safe when driving behind other vehicles under good conditions, you should leave at least one second between your vehicle and the vehicle ahead for each ______ feet of your vehicle’s length.
a)
20
b)
10
c)
30
19.
The air leakage rate for a combination vehicle (engine off, brakes on) should be no more than ___ psi in one minute
a)
4
b)
3
c)
2
20.
Glad hands are used for connecting the:
a)
Kingpin from the tractor to the locking jaws on the glide plate.
b)
Service and emergency air lines from the vehicle to the trailer.
c)
Electric lines from the truck to the trailer.
100 %