MB Air Brake Test 9
- Perfect for first-time and renewal commercial applicants, and those adding endorsements
- Based on 2024 MB commercial driver's licence manual
- Triple-checked for accuracy
- Updated for December 2024
questions
correct answers to pass
passing score
- To test the low air-pressure warning device, lower the air pressure to about
- On each end of a steering axle, should the distance between the center of the camshaft and the clevis pin always be the same?
- Can varying patterns of holes on some models of slack adjusters result in different appearances on each end of an axle, even when they are correctly attached?
- What is the air brake chamber size based on?
- Which statement is incorrect? An inspection of the foundation brake components looks for
- To start the test of the low air-pressure warning device, does the engine need to be running?
- What is the purpose of including external reference points in brake-stroke indicators?
- What type of defect is it if the vehicle does not pass the air-tank drain valves test?
- Which of the following steps is not involved in testing tractor spring brakes?
- What is the effect of brake wear on the brake pushrod stroke?
- Which of the following is not a step in testing the air tank drain valves?
- Closing the trailer air supply valve causes the trailer spring brakes to apply. Which of these can also cause this?
- Is it necessary for drivers to be thoroughly trained on brake-stroke indicators?
- Which step is not involved when testing for trailer spring brakes?
- Which of the following steps is not involved in testing service brakes?
- What issue is implied when oil is detected in any air tank other than the wet tank?
- Which of the following is not a step in checking the operation of the governor?
- What are the most obvious and lasting features used to identify long-stroke brake chambers?
- Which air tank should always be emptied first to prevent the buildup of moisture?
- What is not a step in testing the automatic application of the trailer spring brakes?
- How often should the pushrod stroke be inspected to determine whether the brake adjustment is correct?
- Where else can brake-stroke indicators be fitted?
- Is it normal to discharge a significant quantity of moisture from the remaining air tanks, other than the supply tank?
- If the vehicle does not pass the system air-loss rate test, when should it be repaired?
- What step is not included in testing trailer service brakes?
- What factor determines the variation in brake adjustment limits?
- At what air pressure level should the brake adjustment be inspected?
- Is it necessary to report a sudden increase in the amount of moisture or oil drained from any tank?
- What is the most frequently used brake chamber size?
- What's the maximum permissible air loss when testing system air-loss for a tractor and two or more trailers?
- In order to test the trailer supply valve, which line should be disconnected?
- How can brake application be confirmed when testing the automatic application of the trailer spring brakes?
- What kind of a defect is present if the vehicle fails the test for measuring applied pushrod stroke?
- Which of these statements about long-stroke brake chambers is FALSE?
- What's the maximum permissible air loss when testing system air-loss for a tractor and trailer?
- During the test of the tractor protection valve, the trailer supply valve must be
- If the low-air warning device does not activate or activates under 55 psi, what kind of defect is it?
- What must be demonstrated by a driver to achieve an S air brake endorsement?
- If the pressure drop exceeds the value specified for the vehicle, what kind of defect is it?
- When examining air lines for wear or damage, what is not a concern?
- When testing the governor, the cut-out pressure is found to be below 120 psi. What kind of defect is this?
- Upon determining the correct pushrod stroke, how far should the adjusting bolt be backed off?
- Is brake adjustment inspection necessary regardless of the type of slack adjuster?
- What type of defect can be observed when, during the governor operation inspection, the cut-in pressure is lower than 100 psi?
- Is examining the applied pushrod stroke a dependable method for brake adjustment inspection?
- Which of the following is not done when inspecting foundation brakes?
- Which statement is not correct? When inspecting air compressors...
- Should the brake chambers on the steering axle be of the same size?
- What type of defect is noticed when the cut-out pressure is above 145 psi during the governor operation inspection?
- What is not a defect when inspecting air compressors?