Truck tractors with air brakes that were manufactured on or after March 1, 1997 are required to be equipped with Anti-Lock Braking Systems (ABS). ABS is required in any other type of vehicle with air brakes that was manufactured on or after March 1, 1998.

Anti-Lock Braking Systems (ABS).

If you are unsure if a trailer is equipped with an Anti-Lock Braking System (ABS), look under the vehicle for the electronic control unit and wheel speed sensor wires coming from the back of the brakes.

Look under the trailer for wheel speed sensors coming from the back of the brakes.

Look under the hood for the ABS sticker.

Remove a tire and look for the ABS sensor on the axle.

The purpose of an Anti-Lock Braking System (ABS) is to prevent a vehicle's wheels from locking up when the driver brakes hard on a slippery surface.

Prevent your vehicle from accelerating when going uphill.

Air Brakes Endorsement Test | Oregon 2025 #2

Train for FREE online with our Oregon 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 OR 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

Air Brakes Endorsement Test | Oregon 2025 #2

1 . During an inspection, slack adjusters on S-cam brakes should not move more than:

2 . Truck tractors with air brakes that were built on or after March 1, 1997 are equipped with:

3 . To confirm that a trailer has ABS, you can:

4 . Air brakes use ____ to function.

5 . ABS brakes:

6 . What color malfunction lamps do vehicles equipped with ABS have?

See the exact questions that will be on the 2025 DMV exam.

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