Air Brakes #2
Air Brakes Endorsement Test | Minnesota 2026 #2 Page 2 of 4
Train for FREE online with our Minnesota 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 MN Class A/Class B driver license in 2026, 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.
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7 . The ____ between an air compressor and reservoir tank prevents air from escaping if the air compressor has a leak.
A one-way check valve is required to be between an air compressor and the first main reservoir. This valve prevents air from escaping the system if the air compressor develops a leak.
8 . When braking with ABS, you should:
When operating a vehicle with an Anti-Lock Braking System (ABS), you should apply your brakes in the same manner as you would if operating a vehicle without ABS.
9 . To ensure normal stopping power, drivers of vehicles equipped with a front brake limiting valve should:
Keep the control at the halfway mark.
Some pre-1975 vehicles have a front brake limiting valve, which has "normal" and "slippery" settings. The idea behind these valves was to limit the air pressure available to the front brakes when driving on slippery surfaces, and thereby reduce the danger of a front-wheel skid. Studies have found that this is not actually a concern, so if your vehicle has a front brake limiting valve, leave it in the "normal" position.
10 . If the air pressure warning light comes on, you should:
Safely exit the roadway and stop.
If the low air pressure warning signals activate, it is essential that you bring the vehicle to a safe stop while you are still able to control the brakes.
11 . An alcohol evaporator removes alcohol from the air brake system.
Some air brake systems contain an alcohol evaporator. This device introduces alcohol into the braking system to inhibit the formation of ice.
12 . A low air pressure warning signal:
A vehicle with air brakes must be equipped with a low air pressure warning signal. If the warning signal goes off while a vehicle is being driven, the driver should bring the vehicle to a complete stop and have the system repaired.
2026 Minnesota | Frequently Asked Questions
To secure a CDL Doubles/Triples endorsement in Minnesota, you must first possess a valid CDL. You then need to study the relevant section in the Minnesota Commercial Driver's Manual and pass the written knowledge test at a DVS exam station. The endorsement will be added to your CDL upon passing the test.
To obtain a CDL Doubles/Triples license, you must first hold a valid Commercial Driver's License (CDL). Then, study the relevant sections in your state's Commercial Driver's Manual. After studying, take and pass the Doubles/Triples endorsement knowledge test at your local DMV. This endorsement will be added to your CDL upon passing.
No specific experience or training is legally required to obtain a CDL Doubles/Triples endorsement. However, you need to have a valid CDL. You must study the relevant sections of your state's Commercial Driver's Manual and pass the written knowledge test. Practical experience or training driving such vehicles can be beneficial but is not mandatory.
Yes, to obtain a CDL Doubles/Triples endorsement, you are required to pass an additional written knowledge test. This test focuses on specific rules and safety regulations for driving double and triple trailers. The specific content of the test can be found in your state's Commercial Driver's Manual.
Actually, there is no specific skills test or road test required for the Doubles/Triples endorsement on your CDL. You only need to pass a written knowledge test. This focuses on understanding the handling and safety rules for double and triple trailers, such as coupling and uncoupling, inspecting doubles and triples, and checking air brakes.
No, it's not permissible. In Minnesota, like in all states, you must have a valid Commercial Driver's License (CDL) with a Doubles/Triples endorsement to legally operate double or triple trailers. Operating these vehicles without the proper endorsement can result in serious penalties, including fines and suspension of your driving privileges.
You can add the Doubles/Triples endorsement to your current commercial driver's license (CDL). You don't need to initiate a new application for a CDL. However, you will need to pass the Doubles/Triples written knowledge test and pay the required fees to add this endorsement to your existing CDL.
Yes, there are limitations. While a CDL Doubles/Triples endorsement allows you to drive vehicles with more than one trailer, it doesn't permit you to drive all types of commercial vehicles. For instance, if you want to drive a school bus or a tanker truck, you would need additional endorsements. Also, federal regulations limit the overall length of these vehicles.
In Minnesota, the maximum weight limit for double/triple trailers is 80,000 pounds. The maximum length for a double trailer is 81 feet 6 inches. For a triple trailer, the length should not exceed 100 feet. These limits can vary based on road and bridge laws, so always check local regulations.
Yes, there are specific safety guidelines. Drivers with a CDL Doubles/Triples endorsement must follow regulations regarding securement of cargo, regular vehicle inspections, and maintaining safe following distances. They must also be trained in coupling and uncoupling of units and be aware of the high rollover risk associated with these types of vehicles due to their length and weight.