FREE CDL Combination Vehicles Practice Test Online | Colorado 2024

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

Train for FREE online with our Colorado 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 CO 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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To Pass

1 . If you need to back your trailer but cannot back up in a straight path, you should:

Always turn to your right. If you need to back your trailer but cannot back up in a straight path, you should back on a curved path toward the driver's side of the vehicle. This will permit you the best possible visibility while backing.

2 . To test the trailer service brakes, you should:

Move the vehicle forward slowly and apply the brakes with the hand control. 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.

3 . In a vehicle equipped with an automatic tractor protection valve, the valve will pop out when:

Air pressure is above 45 psi. In vehicles equipped with an automatic tractor protection valve, the valve will pop out if air pressure drops to a level between 20 and 45 psi. When the valve pops out, the protection valve will close, stopping the flow of air.

4 . An Anti-Lock Braking System (ABS):

Assists with the operation of brake lights. The function of an Anti-Lock Braking System (ABS) is to prevent a vehicle's wheels from locking up during hard braking.

5 . 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.

6 . Before backing your tractor under the trailer, make sure your trailer brakes are:

Dry. Correctly following the steps to couple and uncouple trailers is vital to safely operating a combination vehicle. Before backing your tractor under the trailer while coupling, make sure your trailer brakes are locked.

7 . Fully-loaded rigs:

Should not be driven. Because the weight of cargo gives them a higher center of gravity, fully-loaded rigs are 10 times more likely to roll over in a crash than empty rigs.

Wait, before you go

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