FREE CDL Combination Vehicles Practice Test Online | District Of Columbia 2024 Page 2 of 3
Train for FREE online with our District Of Columbia 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 DC 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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8 . If a trailer begins to skid, the driver should:
Accelerate.
If your trailer starts to skid while you are braking, you should release the brakes and allow them to begin to regain traction. Once its wheels have regained their grip on the road, the trailer will begin to straighten out and follow the tractor.
9 . Failure to keep the fifth wheel plate properly greased could:
Affect the lights.
Failure to keep the fifth wheel plate properly lubricated can create friction between the tractor and trailer, causing steering problems.
10 . To prevent a rollover, a driver should:
Turn quickly.
Rollovers can happen when a combination vehicle is turned too quickly. To help prevent the risk of rollover, it is important to keep the vehicle's center of gravity low by loading cargo as close to the ground as possible.
11 . When glad hands are coupled, the seals should be pressed together at an angle of:
90 degrees.
When coupling, be sure to couple the proper glad hands. When glad hands are connected, the seals should be pressed together at a 90-degree angle.
12 . Rollovers happen when:
ABS is working effectively.
Rollovers happen when a vehicle is driven too fast. To reduce the risk of rollover, make sure the weight of cargo is loaded low to the ground, and that you take turns and curves slowly.
13 . A trailer will be most likely to swing around when:
The wheels are rotating.
An empty trailer will require a longer stopping distance than a loaded trailer. Additionally, a trailer is most likely to swing out and strike other vehicles when it is lightly loaded or empty.
14 . When driving a combination rig, following distance should be:
Longer than when driving a single vehicle.
