This endorsement is required if the driver will pull two or three trailers. To receive this endorsement, applicants must pass a test. The test consists of 20 multiple choice questions. To pass, the applicant must answer at least 16 questions correctly. Each question has three or four possible answer choices. Test questions come from the South Dakota Commercial Driver License Manual. Questions come from chapters covering: Driving Safely, Air Brakes (if applicable), Combination Vehicles and Doubles and Triples. The Double/Triple endorsement can be used with the Class A CDL.
Number of Question
1. If there is ice on the front of your side mirror:
If your mirrors or wiper blades become icy while you are driving, you can expect the road surface to be icy as well.
2. Why should the steps of a pre-trip inspection be done in the same order each time?
Doing an inspection the same way every time will help you learn the necessary steps. You will be less likely to forget a step if you get into a routine.
3. When should the trailer hand valve be used?
The trailer hand valve, also called the trolley valve or Johnson bar, is used to work the trailer brakes. It should be used only to test the brakes. Using it while a vehicle is in motion could cause a skid.
4. When near a railroad crossing:
You should never assume that you will hear an approaching train. The train operator may fail to sound the horn, or the use of a train's horn may be prohibited in a specific area. Even if the train does sound its horn, noise from inside your own vehicle may prevent you from hearing the train until it is dangerously close.
5. When driving a vehicle equipped with an Anti-Lock Braking System (ABS), you should:
When driving a tractor-trailer combination that is equipped with an Anti-Lock Braking System (ABS), you should brake in the same manner that you would if the vehicle was not equipped with ABS.
6. When driving in fog, you should:
If you must drive in fog, you should use your low beam headlights and fog lights to maximize your visibility. Using high beam lights will only make it more difficult for you to see.
7. When inspecting the exhaust system, which of the following should not cause concern?