The CDL doubles and triples endorsement test will examine your knowledge of pulling double/triple trailers, coupling and uncoupling, inspecting doubles and triples, and checking air brakes. In order to receive your Doubles and Triples endorsement, it is required that you pass the state’s official CDL written Knowledge exam.

Doubles & Triples Endorsement Test 01

1 / 30

On long downgrades, your trailer brakes should be used...?

2 / 30

On converter dollies with spring brakes, you should release them with...?

3 / 30

In comparison with other commercial vehicles, doubles/triples are...?

4 / 30

You are driving a 110 foot long combination vehicle at 55 mph. What should your following distance be?

5 / 30

When inspecting a double/triple combination, you should give special attention to...?

6 / 30

If you are coupling your second trailer and it doesn't have spring brakes, you can apply the emergency brakes by...?

7 / 30

When driving a double/triple combination, compared to a straight truck or single, your following distance should be...?

8 / 30

For the safest handling on the road, your most heavily loaded trailer should go...?

9 / 30

In a double/triple combination, which of these is the most likely to turn over?

10 / 30

The most important thing to do if your vehicle starts skidding is to...?

11 / 30

Corners when driving a double/triple should be taken...?

12 / 30

When driving a double/triple combination, you need to plan far ahead so that you can keep your driving...?

13 / 30

When making a lane change in a double/triple combination, you must check your mirrors...?

14 / 30

Compared to smaller commercial vehicles, double/triple combinations need more...?

15 / 30

Why are double/triple combinations more likely to skid in adverse conditions?

16 / 30

A converter gear on a dolly is...?

17 / 30

In which of these environments should you be especially cautious about tipping over a double/triple?

18 / 30

When driving a double/triple combination, you should avoid changing lanes near...?

19 / 30

When driving a double/triple combination which is 90 feet long at 30 mph, how much following distance should you allow?

20 / 30

In a combination vehicle on slippery roads, you should not use...?

21 / 30

If you have any doubts about the brakes on your second trailer when connecting, you should...?

22 / 30

When driving a double/triple, to prevent rollover you must steer...?

23 / 30

When parking a double/triple combination, you should arrange things so that you can...?

24 / 30

A converter dolly equipped with antilock brakes will have a yellow lamp...?

25 / 30

With a double/triple combination, which of these will take longer to stop?

26 / 30

When taking a curve in a double/triple combination, you should slow down to a safe speed before entering, then during the curve you should...?

27 / 30

If your speed doubles, your stopping distance increases...?

28 / 30

Compared to other commercial vehicles, doubles/triples have...?

29 / 30

If a converter dolly has air brakes, you should release them by...?

30 / 30

Converter dollies will have antilock brakes if they were built on or after March 1...?

Your score is


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