Combination #2
Combination Vehicles Practice Test | Texas 2025 #2
Train for FREE online with our Texas 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 TX 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 . If a trailer's spring brakes do not release when you push the tractor air supply control, you should:
Drive normally without checking anything.
It is important that all of your vehicle's equipment is in proper working condition before you begin a trip. If a trailer's spring brakes do not release when you push in the tractor air supply control, you should make sure the air line connections are properly attached and sealed.
2 . Air pressure in the ____ air line is controlled by either the foot brake or trailer hand brake.
Auxiliary
Air pressure in the service air line is controlled by either the foot brake or trailer hand brake. The service air line is also known as the control line or signal line. This line is connected to relay valves, which allow the trailer brakes to be applied more quickly than would otherwise be possible.
3 . Starting in which year were newly manufactured trailers required to have ABS?
2004
All trailers and converter dollies manufactured on or after March 1, 1998 must be equipped with Anti-Lock Braking Systems (ABS).
4 . An air supply control in its "emergency" position will:
Accelerate the vehicle.
Tractor protection controls in older vehicles may be operated by levers instead of knobs. If an air supply control is set in its "emergency" position, the air supply will be stopped and the trailer emergency brakes will be applied.
5 . ____ are the cause of more than half of all accident-related truck driver deaths.
Pedestrians
More than half of all accident-related truck driver deaths are a result of truck rollovers. To help prevent a rollover, be sure to load cargo low to the ground and centered on your rig. Take corners slowly and carefully.
6 . A lightly-loaded combination vehicle will stop more slowly than a fully-loaded vehicle because:
The suspension springs only operate when a trailer reaches a minimum weight.
An empty combination vehicle will come to a complete stop more slowly than a fully-loaded vehicle. The stiff suspension springs and strong brakes will have lower traction on a light trailer than they would if the vehicle carried more weight.
7 . To help prevent rollovers, you should:
Keep the load on one side of the trailer.
To lower the risk of a rollover, load your cargo as closely to the ground as possible. To further reduce this risk, take curves and corners slowly.
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2025 Texas | Frequently Asked Questions
To secure a CDL Doubles/Triples endorsement in Texas, you need to have a valid CDL license first. Then, study the Texas CDL handbook's section on Doubles/Triples endorsement. Afterwards, schedule an appointment at your local DMV to take the written test. Upon passing, you'll receive your endorsement. Remember, some employers may require additional on-the-job training.
To obtain a CDL Doubles/Triples license in Texas, you need to have a basic CDL license first. Then, pass the Doubles and Triples Endorsement Test which covers coupling and uncoupling, inspecting doubles and triples, and checking air brakes. Additionally, you must pass a vision test and provide proof of medical fitness.
While Texas doesn't require specific experience for a CDL Doubles/Triples endorsement, it's recommended to have practice handling such large vehicles. A CDL training course can provide this. You must pass a written test on handling double/triple trailers. Knowledge of coupling/uncoupling, inspecting trailers and air brakes is necessary. Professional training can greatly improve your chances of passing the test.
Yes, to obtain a CDL Doubles/Triples endorsement in Texas, you must pass an additional written test. This test covers information specific to driving double and triple trailers such as coupling and uncoupling, inspecting doubles and triples, and the proper procedures for pulling double/triple trailers. No additional road test is required for this endorsement.
The CDL Doubles/Triples endorsement test in Texas is a written exam, not a skills test. It focuses on knowledge such as how to couple and uncouple correctly, inspecting doubles and triples, and checking air brakes. You'll need to understand safe driving techniques for these larger vehicles, but you won't perform actual driving maneuvers during the test.
No, it's not permissible to operate double/triple trailers without a valid CDL Doubles/Triples endorsement in Texas. The endorsement is a legal requirement, demonstrating that the driver has the necessary knowledge and skills to handle such large vehicles safely. Driving without the appropriate endorsement could result in penalties, fines, or even loss of your CDL.
You can add 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 you pass, the Texas Department of Public Safety will add the endorsement to your existing CDL.
Yes, there are constraints for drivers with a CDL Doubles/Triples endorsement. For instance, these drivers must comply with specific weight and length regulations for their vehicles. They may also face restrictions related to hazardous materials transport. Additionally, they must adhere to hours-of-service rules set by the Federal Motor Carrier Safety Administration to ensure safe driving practices.
In Texas, the maximum legal weight for a semi-truck is 80,000 pounds without an overweight permit. The maximum length for a single trailer is 59 feet, while double trailers can be up to 28.5 feet each, and triple trailers up to 28 feet each. However, triple trailers are not legal on all roads in Texas.
Yes, there are specific safety guidelines for driving double/triple trailers. Drivers must ensure proper coupling and uncoupling of units, maintain safe following distance, and manage high-speed and curve control. They must also be aware of the "crack-the-whip" effect that can occur when changing lanes or turning. Furthermore, drivers must abide by Federal Motor Carrier Safety Administration regulations for hours-of-service.
