Combination #1
Combination Vehicles Practice Test | Colorado 2026 #1 Page 3 of 3
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 2026, 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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15 . A shut-off valve:
Should always be open.
Shut-off valves are used in air supply lines to control the passage of air from one trailer to another. The rear shut-off valve should always be closed to prevent air from leaving the braking system.
16 . After coupling, there should be ____ between the upper and lower fifth wheel.
Three inches of space
Before a trip, be sure to inspect all couplings. There should be no space between the upper and lower fifth wheel.
17 . Driving a combination vehicle ____ than driving a single vehicle.
Is safer in inclement weather
Driving a combination vehicle usually requires more skill than driving a single vehicle. Combination vehicles are generally longer and heavier than single commercial vehicles.
18 . 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.
19 . Push in the trailer air supply control to:
Supply the trailer with air.
Push in the trailer air supply control to supply the trailer with air. Pull out the trailer air supply control to turn off the air supply and activate the emergency brakes.
20 . When traveling more slowly than 40 mph, maintain at least ____ of following distance per every 10 feet of your vehicle.
Four seconds
At speeds below 40 mph, you should allow at least one second of following distance for every 10 feet of your vehicle. Follow the same formula when traveling at faster speeds, then add one additional second to your following distance. Remember that larger vehicles require more space to stop than smaller vehicles.
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2026 Colorado | Frequently Asked Questions
To secure a CDL Doubles/Triples endorsement in Colorado, you must already hold a valid CDL. You'll need to pass a knowledge test on handling large trucks with multiple trailers. After passing, the endorsement will be added to your CDL. Remember, this endorsement does not cover the operation of motorcycles or school buses.
To obtain a Colorado CDL Doubles/Triples license, you should first have a valid Colorado CDL. Then, you'll need to pass the Doubles and Triples endorsement test. This test covers topics like coupling and uncoupling, inspecting doubles and triples, and handling. After passing the test, the endorsement will be added to your CDL.
While Colorado doesn't specifically require specialized training for a CDL Doubles/Triples endorsement, it's highly recommended. Training can ensure you're prepared for the knowledge test and safe operation of these vehicles. Experience driving a single trailer truck may also be beneficial, but isn't required. The key requirement is passing the endorsement knowledge test.
Yes, to obtain a CDL Doubles/Triples endorsement in Colorado, you must pass a written knowledge test. This exam focuses on the safe operation and handling of large trucks with multiple trailers. It's important to study thoroughly, using resources like the Colorado CDL Handbook, to ensure success on this test.
For the CDL Doubles/Triples endorsement in Colorado, you're not required to perform a skills or road test. The endorsement solely requires passing a written knowledge test. This test covers topics like coupling and uncoupling, inspecting doubles and triples, and managing the vehicles on the road. Practical skills are important for safe driving but aren't formally tested for this endorsement.
No, it is not permissible to operate double or triple trailers in Colorado without a valid CDL Doubles/Triples endorsement. This endorsement is necessary to ensure that drivers have the specialized knowledge and skills required to safely operate such vehicles. Driving without the proper endorsement can result in legal penalties.
In Colorado, you can add the CDL Doubles/Triples endorsement to your existing commercial driver's license. You don't need to initiate a new application for a separate license. However, you must pass the written knowledge test specific to doubles/triples operation. After passing, the endorsement is added to your current CDL.
Yes, even with a CDL Doubles/Triples endorsement, Colorado drivers must adhere to specific rules. These include a maximum trailer length of 28.5 feet for each unit in a set of doubles, and the total weight of all units combined cannot exceed 80,000 lbs. Also, drivers must follow all federal and state transportation laws, including hours of service regulations.
In Colorado, the maximum legal weight for a vehicle, including double or triple trailers, is 80,000 pounds. The maximum length for a single trailer is 57 feet 4 inches. For double/triple trailers, the combined length should not exceed 100 feet. However, these restrictions may vary depending on road and bridge limits.
Yes, safety is paramount when operating double/triple trailers. Drivers must follow federal and state laws, including speed limits and hours of service regulations. They should also be well-versed in coupling and uncoupling procedures, inspecting the coupling system regularly. Additionally, they must understand the high rollover risk associated with these vehicles and ensure proper cargo distribution to prevent accidents.
