Free Iowa CDL Double/Triple Trailers Practice Test 2022

Do you know how to pair double or triple trailers? If you are planning to take the CDL double/triple trailer endorsement test, make sure to know it! Our Iowa CDL Practice Test has the same questions as the real exam which is based on the Iowa CDL Manual. It covers most of the subject areas on the Double/Triple Trailers Test such as pulling double and triple trailers, the risk of rollover, managing space, and special considerations when hauling multiple trailers. In addition, each question has a detailed explanation that will help you understand the concept and answer future questions about it correctly. If you don't get the pass right away, you can take this CDL practice test an unlimited number of times to make sure you learn all the questions. Let’s try our Free Iowa CDL Double/Triple Trailers Practice Test today and pass your CDL endorsement exam! Good luck and keep driving safely!

Our CDL practice tests:
Based on 2022 IA commercial driver's license manual
Full answers + detailed explanations
Perfect for first-time, renewal applicants
IA CDL Double/Triple Trailers Test format:
20 questions
16 correct answers to pass
80% passing score
List of questions
1.
The part of the combination vehicle most likely to turn over is the:
2.
What is the purpose of a front-brake limiting valve?
3.
Automatic slack adjusters ________.
4.
How do air-operated disc brakes work?
5.
Air brakes take longer to stop than hydraulic brakes because _______.
6.
You will test that the trailer service brakes are working by:
7.
To check if the converter dolly is securely coupled to the rear trailer you should:
8.
You want to hook your combination to a second trailer that has no spring brakes. To do this without wheel chocks you should:
9.
When uncoupling twin trailers you should park:
10.
Which of these statements about quick steering movements and doubles/triples is true?
11.
The trailer air supply control should pop out when the air pressure falls into the pressure range of:
12.
If the dolly has spring brakes, release them with:
13.
When driving doubles or triples in adverse or slippery weather conditions, all of the following are true except:
14.
How should the air leakage rate be tested?
15.
When you need to apply more pressure to help your brakes work normally effectively, this means that your brakes are fading. Which of the following can cause fading brakes?
16.
Why should air tanks be drained completely?
17.
If you have manual transmission _________.
18.
Which of the following factors explains why the total stopping distance for air brakes is longer than that for hydraulic brakes?
19.
Why should you drain water from compressed air tanks?
20.
When inspecting doubles and triples shut-off valves, which of the following is true?