FREE CDL Combination Vehicles Practice Test Online | Utah 2024
Train for FREE online with our Utah CDL combination vehicle test. The official exam test consists of several obligatory parts, with all of them checking your knowledge of different blocks of road rules. If you need to obtain a UT combination license in 2021, practice as much as possible. Free sample tests published on our website will help you check and improve your knowledge and boost your grades. Please bear in mind that DMV requirements for issuing a combination license may vary from state to state.
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1 . What is another name for the service line?
The power line
The trailer service air line is also referred to as the control line or signal line.
2 . Trailers with low underneath clearance can present challenges when driving over:
Railroad-highway crossings may be difficult to cross when pulling a trailer with a low underneath clearance. In particular, both low-slung units and single-axle tractors pulling long trailers are especially challenging to drive over raised crossings.
3 . What does the trailer air supply control look like?
It is a circular orange knob.
On newer vehicles, the trailer air supply control is an eight-sided red knob. It's used to control the tractor protection valve.
4 . In an empty combination vehicle, the stiff suspension springs and strong brakes will have:
An empty combination vehicle will come to a complete stop more slowly than a fully-loaded vehicle. With less weight in a trailer, the stiff suspension springs and strong brakes will have lower traction than they would if the vehicle carried more weight.
5 . What can the “crack-the-whip” effect do?
Make trucks decelerate.
The "crack-the-whip" effect can cause a trailer to turn over during a lane change. To avoid this phenomenon, drivers should make lane changes at slow, safe speeds.
6 . The best way to notice if a trailer has begun to skid is to:
Feel the tractor move.
The easiest way to become aware that your trailer has begun to skid is to observe it in your mirrors. Checking your trailer in your mirrors will also allow you to spot any skidding at the earliest possible moment.
7 . In a sudden turn, the ____ trailer is the most likely to turn over.
First
When making a turn, be sure to steer gently and smoothly. Making a quick turn while pulling trailers is dangerous and can increase the risk of the last trailer rolling over.
8 . Before a drive, ensure that air flows to all trailers by:
Rolling each trailer down a hill and testing the brakes.
