Combination Vehicles · Practice test 3

Question 1Not answered

Why should you be extra cautious about skid risk on bridges and overpasses in cold weather?

1. Bridges have noticeably better traction than regular pavement in cold weather because of their steel surface material
2. Bridges are always treated with salt before other roads
3. Bridge surfaces are unaffected by temperature
4. Bridges and overpasses can freeze before the rest of the road because cold air circulates both above and below the surface

Question 2Not answered

If the trailer's ABS malfunctions but the tractor's ABS still works, how should this affect a driver's approach to braking?

1. Brake with extra caution, since the trailer wheels could still lock up and contribute to a skid
2. No adjustment is needed since the tractor's ABS automatically covers braking for the whole combination
3. The vehicle should not be driven under any circumstances
4. Brake only with the parking brake until repairs are made

Question 3Not answered

Why does slowing down before a curve, rather than during it, help prevent skids in a combination vehicle?

1. It lets the vehicle take the curve at a speed the tires can grip without adding braking force on top of the turning force
2. It has no real effect, since curves are equally risky at any speed
3. It only matters for the trailer's cargo, not for skid risk
4. Braking during the curve always provides better control than braking before entering it, regardless of speed

Question 4Not answered

You notice smoke coming from one of the trailer's wheels while driving. What should this signal to you?

1. A sign that the tires are simply new and breaking in
2. An indication the trailer needs more air in that tire
3. A possible brake or wheel bearing problem serious enough to stop and inspect right away
4. Normal heat from everyday driving that doesn't need any attention or a closer look at the wheel

Question 5Not answered

What should you check about the space between the tractor frame and the trailer's nose (the 'apron') during inspection?

1. Nothing, since this gap has no safety relevance
2. That the gap is wide enough to fit a hand comfortably between the apron and the tractor's frame
3. Only whether the gap is aesthetically even on both sides
4. That there is no dangerous gap suggesting the trailer is not fully seated on the fifth wheel

Question 6Not answered

What is the best way to avoid most skids in a combination vehicle in the first place?

1. Keep both hands loose on the wheel so it can correct itself
2. Make all steering, braking, and acceleration changes early and gently, especially in poor conditions
3. Drive at the posted speed limit regardless of road conditions
4. Brake as late as possible so you always have more time to react to whatever changes up ahead

Question 7Not answered

During a pre-trip inspection, why should you check the glad hand seals where the tractor and trailer air lines connect?

1. Glad hand condition has no effect on braking as long as they're connected
2. A worn or cracked seal can leak air and weaken the trailer's brakes
3. Seals only matter for keeping rain out of the connection
4. Glad hands are only there to hold the lines in place when parked, they carry no air themselves

Question 8Not answered

Why should you avoid making sudden lane changes in a combination vehicle on a wet or icy road?

1. Sudden lane changes are always just as safe as gradual ones, even in wet or icy conditions
2. It only matters for empty trailers
3. A sudden lateral movement can exceed the available traction and start a skid, particularly with reduced grip
4. Wet or icy roads have no effect on how a lane change should be performed

Question 9Not answered

What should a driver generally prioritize if an emergency requires choosing between hitting a soft shoulder area or continuing toward a more serious hazard ahead?

1. Choosing the lesser hazard, such as the shoulder, over the more serious one ahead, while maintaining as much control as possible
2. Closing your eyes until the situation resolves
3. Always braking as hard as possible right away regardless of what is ahead or how much room there is to work with
4. Continuing straight no matter what is directly ahead

Question 10Not answered

When backing a combination vehicle into a tight space, what is the safest practice?

1. Back quickly to reduce the time spent maneuvering
2. Back without stopping to check progress, to keep a smooth motion all the way in
3. Rely only on the mirrors since a helper can be a distraction
4. Use a helper outside the vehicle whenever possible, agreeing on signals beforehand

Question 11Not answered

Why should you increase your following distance even further than usual when driving a combination vehicle in fog or heavy rain?

1. Following distance rules only apply in clear weather
2. Reduced visibility and traction both extend the distance needed to see a hazard and then stop for it
3. Fog and rain only affect how far ahead you can see, not how far the vehicle actually needs to stop
4. Increasing distance in poor weather is a courtesy, not a safety need

Question 12Not answered

How does recovering from a drive-wheel skid differ from recovering from a trailer skid?

1. A drive-wheel skid is corrected only by accelerating harder
2. Both a drive-wheel skid and a trailer skid are handled the same way, by braking hard immediately to regain traction on whichever axle lost it
3. In a drive-wheel skid you stop the wheel spin and steer straight; in a trailer skid you keep the units aligned by steering, not braking
4. There is no meaningful difference between the two

Question 13Not answered

Why does inspecting a combination vehicle take longer than inspecting a straight truck?

1. Inspection time is identical regardless of vehicle configuration
2. Combination vehicles actually require less inspection time overall since trailers rarely develop mechanical problems
3. It only takes longer because of the extra tires, with nothing else to check
4. There are more components to check, including the coupling, trailer landing gear, and separate trailer air and electrical systems

Question 14Not answered

Why should you raise the landing gear fully before driving away after coupling a trailer?

1. Leaving it partially down can let it drag, catch on the road, or be torn off while driving
2. Landing gear position has no effect at all once the fifth wheel is fully locked around the kingpin
3. It only affects the trailer's fuel economy
4. It is only necessary if the trailer will sit for more than a day

Question 15Not answered

Why should the trailer supply valve (the red button or valve) be closed before disconnecting the air lines during uncoupling?

1. Closing it first sets the trailer brakes so the trailer stays in place once the tractor is disconnected
2. It is only relevant when coupling, not uncoupling
3. It should always be left open during uncoupling to allow for a faster disconnect afterward each time
4. It has no relationship to the trailer's braking during uncoupling

Question 16Not answered

Why should a driver be especially cautious about wind when driving an empty or lightly loaded combination vehicle?

1. Wind has no meaningful effect on any combination vehicle at all once it is already up to speed
2. A lightly loaded trailer offers less resistance to being pushed sideways by strong gusts
3. Empty trailers are always more stable in wind than loaded ones
4. Crosswinds only affect vehicles above legal highway speed

Question 17Not answered

What should you confirm before passing another vehicle with a long combination on a two-lane road?

1. That your combination is shorter than the vehicle you're passing
2. That the vehicle ahead has already signaled it's fine to pass
3. That the road has a marked passing lane, regardless of how much oncoming traffic is approaching in it
4. That there is enough clear distance ahead to complete the pass and return to your lane well before any oncoming traffic

Question 18Not answered

What should a driver do if the coupling appears to be failing while driving, such as unusual movement felt between the tractor and trailer?

1. Speed up to reach the destination before the coupling problem has a real chance to fully fail
2. Slow down gradually and pull off the road safely to inspect the coupling before continuing
3. Ignore the movement since couplings rarely fail once locked
4. Brake as hard as possible immediately regardless of surrounding traffic

Question 19Not answered

What is the recommended response if you feel the rear of the trailer starting to swing out during a turn?

1. Accelerate to pull the trailer back into line
2. Turn the steering wheel sharply away from the swing to try to pull the trailer back in line fast
3. Brake hard immediately to try to stop the swing
4. Ease off the accelerator smoothly rather than braking hard or making a sharp steering correction

Question 20Not answered

While driving, you hit a pothole hard and feel the trailer sway noticeably afterward. What should you do?

1. Steer quickly side to side to cancel out the sway
2. Brake hard immediately to stop the sway
3. Ease off the accelerator and hold a steady course, checking mirrors as the sway settles before deciding whether to stop
4. Accelerate hard to pull the trailer back into a straight line before it has a chance to sway further

Question 21Not answered

You are driving a combination vehicle and the trailer begins to swing out in a skid. What is the correct response?

1. Brake hard to stop the skid quickly
2. Turn sharply away from the direction of the skid to try to straighten the trailer out immediately
3. Stay off the brake and steer to keep the tractor and trailer in line
4. Accelerate to pull the trailer back into line

Question 22Not answered

What is the purpose of doing a walk-around check immediately after coupling, before driving away?

1. To physically confirm the coupling, air lines, electrical connection, and landing gear are all correctly set
2. It replaces the need to pull forward and test the coupling
3. To check the trailer's paint condition
4. It is only a formality with no functional purpose beyond satisfying an internal company checklist policy

Question 23Not answered

What does 'off-tracking' mean when a combination vehicle takes a turn?

1. The trailer's wheels follow a shorter, tighter path than the tractor's wheels
2. A term used only for backing maneuvers, never forward turns
3. A term for a trailer completely leaving the roadway during a turn
4. The trailer's wheels always follow the exact same path as the tractor's wheels

Question 24Not answered

Why do you need extra space to the side of a combination vehicle compared to a single vehicle when a car is merging nearby?

1. A combination vehicle actually has smaller blind spots than a single vehicle because of its extra convex mirrors
2. The trailer's length and width leave less margin for a merging vehicle to misjudge, and the driver has larger blind spots to cover
3. Side space only matters for parking, not for merging traffic
4. Merging traffic always yields automatically to larger vehicles

Question 25Not answered

In a combination vehicle, what typically happens first in a jackknife skid caused by hard braking?

1. The tractor's drive wheels lose traction and the trailer's momentum pushes the tractor sideways
2. The trailer's brakes always fail before the tractor's brakes in every single combination vehicle
3. The steering axle locks up first in every case
4. The fifth wheel disconnects automatically

Question 26Not answered

What is the trailer hand valve actually intended for, as opposed to being used to control a skid?

1. Stopping the vehicle in the shortest possible distance in an emergency, faster than the foot pedal
2. Slowing the combination gradually in normal traffic
3. Replacing the foot brake pedal during long descents
4. Testing that the trailer brakes hold, such as during a pre-trip brake check

Question 27Not answered

What is the safest general response if the trailer begins to fishtail on a slippery road?

1. Ease off the accelerator gradually and avoid abrupt steering or braking inputs
2. Accelerate to pull the trailer straight
3. Turn the wheel sharply in the opposite direction of the fishtail to straighten it out
4. Brake hard to stop the fishtailing immediately

Question 28Not answered

What should you inspect regarding the trailer's brake lines and gladhand seals as part of a combination vehicle check?

1. Nothing additional beyond what is checked on the tractor alone
2. That they are properly connected, not crossed, and free of cracks that could cause an air leak
3. Only that they are the same length as the tractor's lines
4. That they are loosely connected on purpose to allow flexibility while the trailer turns sharply

Question 29Not answered

During a combination vehicle inspection, you notice the trailer's landing gear is bent. What should you do?

1. Use extra chains to compensate for the damage instead of taking the trailer out of service
2. Note it in the logbook and continue as planned
3. Do not use the trailer until the landing gear is repaired
4. Couple carefully and drive at reduced speed

Question 30Not answered

After coupling, you cannot see the kingpin well enough to confirm by eye that it is captured in the fifth wheel's jaws. What should you do?

1. Assume it is fine if the pull test doesn't move the trailer
2. Crawl under the trailer to visually confirm the jaws are closed around the kingpin before driving
3. Skip the visual check if the locking indicator light is not lit either way and trust the pull test
4. Tap the brakes a few times, since a proper coupling always releases a clicking sound