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.
When checking the low pressure warning signal, it should turn on before the pressure drops below what psi?
2.
An application pressure gauge shows how much air you are applying to the brakes. Increased application pressure to maintain the same speed indicates that __________.
3.
With the hand valve on, you should test the trailer brakes by opening the service line valve at the rear of the trailer. When you do this, you should hear:
4.
When you turn with the tractor/triple trailer combination, the wheels that off-track (cheat) the most are:
5.
The increased likelihood of doubles and triples turning over is called:
6.
The air compressor should pump air starting at what psi?
7.
On newer vehicles, the parking brake control knob is typically yellow, but on older vehicles, the parking brake might be what color?
8.
The service brake system ________.
9.
A safety valve that releases air _______.
10.
During a normal drive, the spring brakes are held back by _____.
11.
A danger of a malfunctioning tractor protection valve is:
12.
In tractors and straight trucks spring brakes will come on fully when the air pressure drops to what range?
13.
Wedge brakes and disc brakes are ______ than s-cam brakes.
14.
What is a front brake limiting valve?
15.
When you make an emergency stop, you should _________.
16.
If the air compressor does not have its own oil supply, how is it lubricated?
17.
If the malfunction lamp stays on after the bulb check, __________.
18.
Why is it so crucial to drain your vehicle's air tanks at the end of each day of driving?
19.
When uncoupling the rear trailer, which of these should be done first?
20.
A visual inspection after coupling should show that: