1 / 20
A. 10
B. 12
C. 11
One good rule says you need at least one second for each 10 feet of vehicle length at speeds below 40 mph. At greater speeds, you must add 1 second for safety.
2 / 20
A. Are against the law in most states
B. Make things look smaller and farther away than the really are
C. Do not need to be checked as often as flat mirrors because they show a larger area
The convex mirrors are located below the outside flat mirrors. They are used to monitor the left and right sides at a wide angle. They provide a view of traffic and clearances. These mirrors present a view of people and objects that does not accurately reflect their size and distance.
3 / 20
A. You should avoid traveling next to others when possible
B. Always keep your vehicle to the right side of your lane
C. High winds are not a problem for doubles and triples
Commercial vehicles are often wide and take up most of a lane. Safe drivers will manage what little space they have. You can do this by keeping your vehicle centered in your lane and avoid driving alongside others.
4 / 20
A. A triple rig can stop quicker than a 5-axle tractor semi-trailer due to off tracking
B. A sudden movement with the steering wheel can result in a tipped over rear trailer
C. The rear trailer of a 100-foot triple is less likely to turn over than a single semi-trailer due to the crack the whip effect
To prevent trailers from rolling over, you must steer gently and go slowly around corners, on ramps, off ramps, and curves. A safe speed on a curve for a straight truck or a single trailer combination vehicle may be too fast for a set of doubles or triples.
5 / 20
A. After signaling the change
B. After completing the lane change
C. All answers are correct
D. Right after starting the lane change
Check your mirrors: Before you change lanes to make sure there is enough room. After you have signaled, to check that no one has moved into your blind spot. Right after you start the lane change, to doublecheck that your path is clear. After you complete the lane change.
6 / 20
A. Open the shut off valves at the rear of both trailers
B. Close the shut off valves at the rear of both trailers
C. Open the shut off valves at the rear of the first trailer, and close the shut off valves at the rear of the second trailer
Shut-off valves at rear of trailers, in service and emergency lines. Rear of front trailers: open. Rear of last trailer: closed.
7 / 20
A. Gently pressing the brake pedal while driving through the water
B. Increase engine rpm
C. Drive though quickly
D. Use a lower gear
Slow down and place transmission in a low gear. Gently put on the brakes. This presses linings against brake drums or discs and keeps mud, silt, sand, and water from getting in.
8 / 20
A. the shut-off valves, the converter dolly or dollies, and the air brakes on all trailers
B. the trailers and the radios in the tractor
C. the fifth wheel and the landing gear
To inspect a double or triple, first inspect it just as you would inspect any combination vehicle. Then check that the shut-off valves are open on all trailers but the last trailer. Check each converter dolly to be sure that the pintle hook is properly latched.
9 / 20
A. both of the above are true
B. aggressive drivers may cause trouble for you on the road
C. the vehicle is more likely to roll over or jackknife
Doubles and triples must be driven very smoothly to avoid rollover or jackknife. Therefore, look far ahead so you can slow down or change lanes gradually when necessary
10 / 20
A. Wheel chocks
B. Either answer can be correct
C. The trailers spring brakes and emergency air brakes
Make sure trailer brakes are locked and/or wheels chocked.
11 / 20
A. Counter steering is easier with doubles / triples than with most other vehicles
B. You should put on the brakes at the same time you perform quick steering movements
C. Doubles / triples flip over from quick steering movement easier than many other vehicles
Rearward amplification causes the crack-the-whip effect. Triples have a rearward amplification of 3.5 meaning you can roll the last trailer of triples 3.5 times as easily as a five-axle tractor. A Double has a reward amplification of 2 being twice as likely to roll over as a five-axel trailer.
12 / 20
A. Use only the trailer brakes
B. Go 5 MPH below your safe speed
C. Use stab braking
The use of brakes on a long and/or steep downgrade is only a supplement to the braking effect of the engine. The following are the proper braking techniques: Apply the brakes just hard enough to feel a definite slowdown. When your speed has been reduced to approximately five mph below your "safe" speed, release the brakes. When your speed has increased to your "safe" speed, repeat.
13 / 20
A. Have little braking power because they are small
B. Often do not have spring brakes
C. Usually need a glad hand converter
Converter dollies often do not have spring brakes.
14 / 20
A. A trailer jackknife
B. The rig will stay in a straight line but slide sideways
C. The rig will continue to move in a straight line no matter how much the steering wheel is turned
Doubles and triples must be driven very smoothly to avoid rollover or jackknife. Therefore, look far ahead so you can slow down or change lanes gradually when necessary.
15 / 20
A. March 1998
B. March 2000
C. March 2003
Truck tractors with air brakes built on or after March 1, 1997 require ABS, and other air brake vehicles such as trucks, buses, trailers, and converter dollies built on or after March 1, 1998 require ABS.
16 / 20
A. The types of cargoes it carries make it more likely to have problems
B. Its design makes it more likely to have problems
C. There are more critical parts to check
There are more things to inspect on a double or triple combination vehicle than on a single vehicle. Many of these items are simply more of what you would find on a single vehicle. For example, tires, wheels, lights, reflectors, etc. However, there are also some new things to check.
17 / 20
A. Good drivers shift their attention back and forth, near and far
B. All answers are correct
C. Many drivers do not look far enough ahead of their truck
D. At highway speed you should look up to 1/4 mile ahead of your truck
Most good drivers look at least 12 to 15 seconds ahead. That means looking ahead the distance you will travel in 12 to 15 seconds. At lower speeds, that's about one block. At highway speeds it's about a quarter of a mile.
18 / 20
A. The rear trailer of a double
B. The rear trailer of a triple
C. A full trailer behind a truck
Due to rearward amplification a double is twice as likely, and a triple is 3.5 times more likely to roll over than a five-axel trailer.
19 / 20
A. third; two or three
B. fifth; two or three
C. fifth; one or two
A converter gear on a dolly is a coupling device of one or two axles and a fifth wheel by which a semitrailer can be coupled to the rear of a tractor trailer combination forming a double bottom rig.
20 / 20
A. to lower its landing gear
B. to slowly pull clear of it
C. to disconnect the safety chains
Lower dolly landing gear.
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