20 Tests

CDL Combination Vehicles Practice Test Online | Louisiana 2021

Train for FREE online with our Louisiana 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 LA combination license in 2021, practice as much as.. Read More

Train for FREE online with our Louisiana 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 LA 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 . The "crack-the-whip" effect can:

Trailers can overturn as a result of the "crack-the-whip" effect. The last trailer in a combination is the most prone to tip over due to this effect. Drivers should be aware of the rearward amplification of their specific vehicles and drive accordingly.

2 . The trailer hand valve:

Never use the trailer hand valve while parking because doing so may release the air pressure from the braking system, releasing the brakes that are holding the vehicle in place. Instead, use the parking brake or wheel chocks.

3 . When testing ____, you should apply your vehicle's brakes with the hand control while moving the vehicle forward slowly.

To test the trailer service brakes, you should first ensure that the braking system has a normal air pressure level, then release the parking brake. You should then move the vehicle forward slowly and apply the brakes with the hand control. If the trailer service brakes are working properly, you will feel the brakes activate.

4 . Older trailers are not equipped with spring brakes. This means that if the air supply for a vehicle's air braking system leaks away:

Older trailers do not have spring brakes. This means that if the air supply in an older trailer's air tank has leaked away, there will be no working brakes connected to the trailer and its wheels will turn freely.

5 . Before a trip, you can make sure air flows to all trailers by:

Before a trip, ensure that air in the air brake system reaches all trailers. Do this by waiting for air pressure to build, then sending air to both the emergency and service lines and opening the shut-off valves on the rear of the last trailer. If air escapes from the shut-off valves in the rear of the combination, the air is being supplied to the entire vehicle.

6 . Combination vehicles are usually:

Driving combination vehicles requires more skill than driving single commercial vehicles. Combinations are generally longer, generally heavier, and are more vulnerable to rollover.

7 . If a load is placed on one side of a trailer, the trailer:

Positioning the weight of a load on one side of a trailer may cause the trailer to lean to that side, increasing the risk of a rollover during turns and lane changes.

Wait, before you go

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