Air Brakes Endorsement Test | Mississippi 2025 #2

Train for FREE online with our Mississippi CDL air brake test. The official exam test consists of several obligatory parts, with all of them checking your knowledge of different blocks of road rules. If you need to obtain a MS Class A/Class B driver license in 2025, practice as much as possible. Free sample tests published on our website will help you check and improve your knowledge and boost your grades. Please bear in mind that the requirements for CDL may vary from state to state.

Number of Question 25

Passing Score 20

Number of Tests 20

1 . During a static leakage test, what is the maximum leakage rate that is safe for a double combination vehicle?

3 psi in one minute.

6 psi in one minute.

8 psi in one minute.

When performing a static leakage test on a double combination vehicle with air brakes, the leakage rate should be no more than 3 psi in one minute. If the air leaks from the air brake system at a quicker rate, the vehicle should not be driven because something likely needs to be repaired.

2 . At what psi is the safety valve set to open?

100 psi

150 psi

200 psi

500 psi

In an air brake system, the first tank that receives compressed air has a safety valve that releases air if the pressure gets too high. It is usually set to open at 150 psi. If the valve must open, there is a fault in the system that should be repaired by a mechanic.

3 . Spring brakes come on:

When too much air pressure is lost.

When a control on the dashboard is activated.

When the tires have minimal tread depth.

When the brakes are noisy.

Spring brakes come on automatically when air pressure drops to an unsafe psi level. Instead of waiting for the spring brakes to automatically activate, you should safely exit the road as soon as you notice the low pressure warning signal and bring your vehicle to a stop while you are still able to control the brakes.

4 . Which part of the truck is the air compressor connected to?

The transmission

The engine

The radiator

The door latch

In an air brake system, the air compressor is connected to the engine through gears or a v-belt.

5 . If using air tanks with manually operated drains, how often should you drain the tanks?

Every day

Once a week

Once a month

Once every six months

In an air brake system with manually operated drains, the tanks should be drained at the end of each day of driving.

6 . All air tanks must include:

A drain valve.

A lock.

A trap door.

A warning sticker.

Air brake system tanks must contain drain valves. These valves are used to drain accumulated oil and water from the tanks and may be either manually or automatically operated.

Study tip:

Reduce your study time from hours to minutes with a DMV exam “Cheat Sheet”

99.2% of people who use the cheat sheet pass the FIRST TIME

Click Here
Full Cheat Sheet

99.2%

99.2% of people who use the cheat sheet pass the FIRST TIME

2025 Mississippi | Frequently Asked Questions

To secure a CDL Doubles/Triples endorsement in Mississippi, you must already possess a Commercial Driver's License (CDL). You'll need to pass a written knowledge test on handling large trucks with more than one trailer. Study the Mississippi CDL handbook, especially the section on doubles and triples. After passing the test, the endorsement will be added to your CDL.

To obtain a CDL Doubles/Triples license, you must already have a Commercial Driver's License (CDL). You'll need to pass a written knowledge test focused on handling large trucks with multiple trailers. This includes understanding coupling and uncoupling, inspecting doubles and triples, and crucial driving skills. Preparation via the state's CDL manual is highly recommended before taking the test.

While Mississippi does not specifically require specialized training for a CDL Doubles/Triples endorsement, it is highly recommended. The endorsement test covers topics like coupling and uncoupling, inspecting doubles and triples, and pulling double/triple trailers. Studying the CDL handbook and gaining practical experience can significantly improve your chances of passing the test.

Yes, to obtain a CDL Doubles/Triples endorsement, you must pass a specific written knowledge test. This test covers topics such as coupling and uncoupling, inspecting doubles and triples, and important driving skills. It's important to study the CDL handbook, particularly the section on doubles and triples, before taking the test.

The CDL Doubles/Triples endorsement test is a written examination, so no specific driving maneuvers are required. However, the test does assess your understanding of key skills such as coupling and uncoupling trailers, inspecting doubles and triples, and managing the substantial driving differences that come with operating these larger vehicles.

No, it's not permissible. Operating double or triple trailers requires a valid CDL Doubles/Triples endorsement in Mississippi, as well as in all other states. This endorsement ensures that the driver has the necessary knowledge and skills to safely operate these larger, more complex vehicles. Driving without the appropriate endorsement can result in fines and penalties.

Yes, you can append the CDL Doubles/Triples endorsement to your existing Commercial Driver's License. You don't need to initiate a new application for a CDL. However, you will need to pass the Doubles/Triples endorsement knowledge test to add this endorsement to your current CDL.

Yes, there are limitations for drivers holding a CDL Doubles/Triples endorsement. While this endorsement allows you to operate double and triple trailers, it doesn't permit the operation of other commercial vehicles like buses or tank trucks. Also, federal regulations limit the total length of these combinations to 81 feet. All drivers must abide by these and all other relevant rules and regulations.

The maximum weight for a double/triple trailer in Mississippi, with a CDL Doubles/Triples endorsement, is 80,000 pounds. The maximum length for a double trailer is 81 feet. However, the specific weight and length can vary depending on the combination of trailers. It's crucial to comply with these limits to ensure safety and avoid penalties.

Yes, when driving double/triple trailers, drivers must follow specific safety guidelines, including maintaining a safe following distance, avoiding sudden stops or lane changes, and inspecting the coupling devices and cargo regularly. Additionally, drivers must adhere to federal and state regulations regarding hours of service, vehicle weight and length limits, and hazardous materials transport.