Double
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 four possible answer choices. Test questions come from the New Jersey Commercial Driver Guide. 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
Passing Score
1. Truck tractors with air brakes built on or after March 1, 1997 must have:
Explanation
Truck tractors with air brakes built on or after March 1, 1997 must be equipped with Anti-Lock Braking Systems (ABS).
2. An Anti-Lock Braking System (ABS):
Explanation
Anti-Lock Braking Systems (ABS) are compatible with air braking systems. ABS helps maintain control of a vehicle and prevents the wheels from locking up during hard braking on slippery surfaces. ABS can still provide benefits even if is present on only one axle.
3. Test the tractor protection valve by:
Explanation
You should test the tractor protection valve by allowing the air supply to properly charge, turning off the engine, then releasing air from the system by pressing the brake pedal several times. The tractor protection valve should move into its emergency position when psi drops to an unsafe level.
4. When approaching a downgrade, how can you reduce the amount of braking that will be needed?
Explanation
Always shift to a lower gear before starting down a hill. Doing this will help your vehicle maintain a safe speed without you needing to use the brakes too much.
5. Improper coupling is:
Explanation
It is essential that drivers of doubles and triples are able to correctly couple and uncouple their trailers. Improperly coupling and uncoupling trailers is extremely dangerous.
6. In poor weather, the driver of a double or triple should:
Explanation
In adverse weather conditions, special care must be taken when driving a double or triple. They are especially prone to skids, loss of traction, and rollovers.
7. Driving at night is:
Explanation