Air Brakes #1
Air Brakes Endorsement Test | Mississippi 2025 #1 Page 4 of 4
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.
25
20
20
19 . What happens if the air pressure in a system's air tanks falls below 60 psi?
The vehicle should stop.
In an air brake system, a low pressure warning signal should activate if the pressure in the air tanks falls to a level below 60 psi. This signal may be in the form of a warning light or a wig wag.
20 . Which part of the truck is the air compressor connected to?
The door latch
In an air brake system, the air compressor is connected to the engine through gears or a v-belt.
21 . Front wheel braking works:
Under most conditions.
Front wheel braking is effective under all road conditions. It is unlikely that you will experience a front wheel skid, even on ice.
22 . During a static leakage test, what is the maximum leakage rate that is safe for a double combination vehicle?
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.
23 . At what psi is the safety valve set to open?
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.
24 . Brakes can get out of adjustment quickly, especially:
Brakes are particularly prone to getting out of adjustment if they are hot. Be sure to routinely check the adjustment of your brakes. For a vehicle to be safely controlled, all brakes must be properly functioning and adjusted.
25 . When traveling down a steep downgrade, the best way to use your brakes is to:
Apply consistent pressure to the brake pedal all the way down the hill.
On a long or steep downgrade, brakes should only be used to supplement the braking effect of the engine. Apply the brakes just enough to feel a definite slowing down, then release them once you are about 5 mph below your target "safe" speed. Once your vehicle reaches its safe speed again, repeat this process.
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.