Combination #1
Combination Vehicles Practice Test | Idaho 2025 #1
Train for FREE online with our Idaho 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 ID combination license in 2025, 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 . In a vehicle equipped with an automatic tractor protection valve, the valve will pop out when air pressure drops to a level between:
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.
2 . Combination vehicles:
Driving combination vehicles requires more skill than driving single commercial vehicles. Combinations are generally longer, generally heavier, and are more vulnerable to rollover.
3 . When connecting a converter dolly to a second trailer, the trailer height should be ____ the center of the fifth wheel.
When connecting a converter dolly to a second or third trailer, the trailer height should correct. It should be slightly lower than the center of the fifth wheel.
4 . Rearward amplification refers to:
Vehicles with trailers are vulnerable to rollover due to the "crack-the-whip" effect, which is caused by rearward amplification.
5 . Trailers built before ____ are not required to have spring brakes.
Trailers built before 1975 are not required to have spring brakes. When parking a trailer without spring brakes, be sure to use wheel chocks to prevent the trailer from rolling.
6 . How much space should be between the upper and lower fifth wheel?
Before a trip, be sure to inspect all couplings. There should be no space between the upper and lower fifth wheel.
7 . The service air line is often controlled by the foot brake and is attached to the ____ valves.
The service air line carries air and is controlled by either the foot brake or trailer hand brake. The service air line is attached to relay valves, which allow the trailer brakes to be applied quickly.
2025 Idaho | Frequently Asked Questions
To secure a CDL Doubles/Triples endorsement in Idaho, you need to have a valid commercial driver's license (CDL). You will then need to pass the Doubles/Triples Knowledge Test offered by the Idaho Transportation Department. It's also recommended to practice with a qualified trainer before the test to ensure you understand how to safely operate these types of vehicles.
To obtain a CDL Doubles/Triples license, you must already hold a Commercial Driver's License (CDL). You'll need to pass the Doubles/Triples Knowledge Test, which covers coupling and uncoupling, inspecting doubles and triples, and checking air brakes. It's also recommended to have some hands-on training with a qualified instructor to ensure you can safely operate these vehicles.
While Idaho does not specifically require specialized experience or training for a CDL Doubles/Triples endorsement, it is highly recommended. Understanding how to handle these types of vehicles, how to couple and uncouple, and inspecting the vehicle are crucial. This knowledge can be gained through hands-on training with a qualified instructor and studying the CDL manual.
Yes, to obtain a CDL Doubles/Triples endorsement in Idaho, you are required to pass the Doubles/Triples Knowledge Test. This written exam focuses on the specific knowledge and skills needed to safely operate double and triple trailers, including coupling and uncoupling, vehicle inspections, and managing cargo.
During the CDL Doubles/Triples endorsement test in Idaho, you won't have to showcase specific driving skills or maneuvers. The test is knowledge-based and covers topics like coupling and uncoupling, inspecting doubles and triples, and managing cargo. However, practical skills like safely driving, turning, and parking these vehicles are crucial for real-world application.
No, it is not permissible to operate double or triple trailers without a valid CDL Doubles/Triples endorsement in Idaho. This endorsement is required by federal and state law to ensure that drivers have the necessary skills and knowledge to safely operate these larger, more complex vehicles. Operating without the endorsement can result in fines and penalties.
You can append the CDL Doubles/Triples endorsement to your current commercial driver's license. You don't need to initiate a new application for a CDL. However, you must pass the Doubles/Triples Knowledge Test. Once passed, the endorsement will be added to your existing CDL.
Drivers with a CDL Doubles/Triples endorsement must adhere to specific rules. These include restrictions on the maximum combined length of the trailers and the requirement to only drive these vehicles on designated highways. Also, they must follow all general CDL regulations, including hours of service rules, vehicle inspection requirements, and maintaining a clean driving record.
In Idaho, the maximum weight for a commercial vehicle, including double or triple trailers, is 105,500 lbs. The maximum length for a double trailer is 61 feet for the two trailers combined. Triple trailers are not generally permitted except on designated highways and they cannot exceed 95 feet in total length. These restrictions can change, so always check the current regulations.
Yes, there are specific safety guidelines for driving double/triple trailers. Drivers must maintain a safe following distance, anticipate stops, and avoid sudden lane changes. They should also be mindful of the "crack-the-whip" effect during turns. Regular vehicle inspections are mandatory to ensure brake system integrity and correct weight distribution. Additionally, drivers must comply with all CDL rules and federal regulations.