ASE A3 Manual Drive Train and Axles

Micrometer

1. The reading on the outside micrometer above indicates:

  • A. .203 inch.
  • B. .253 inch.
  • C. .253 mm.
  • D. .228 inch.

1.

Micrometer

Answer A is wrong. Answer D is correct.

Answer B is wrong. Answer D is correct.

Answer C is wrong. The micrometer above is inch-based.

Answer D is correct. The inch-based micrometer is graduated in thousandths of an inch. It reads 0.228".

2. After removing a rear brake drum from a light truck with a solid rear axle, the technician notices the backing plate and brake shoes are wet with fluid. Technician A says a leaking wheel cylinder could be causing this contamination. Technician B says a leaking axle seal could be the cause. Who is correct?

  • A. Technician A
  • B. Technician B
  • C. Both A and B
  • D. Neither A or B

2.

Answer A is wrong. Both technicians are correct.

Answer B is wrong. Both technicians are correct.

Answer C is correct. Axle seals keep lubricating while keeping water and debris out. They fail and leak from wear or damage. The rubber lip shrinks and hardens, and the garter spring weakens, allowing differential fluid to bypass the seal, dripping onto the backing plate and contaminating the brake shoes.

Answer D is wrong. Both technicians are correct.

3. Technician A says to use a dial indicator to check for flywheel runout. Technician B says to use a dial indicator to check for crankshaft endplay. Who is correct?

  • A. Technician A
  • B. Technician B
  • C. Both A and B
  • D. Neither A or B

3.

Answer A is wrong. Both technicians are correct.

Answer B is wrong. Both Technicians are correct.

Answer C is correct. To check the lateral runout on a conventional flywheel, place the tip of the dial indicator on the flywheel's surface and then rotate the flywheel. The lateral runout is the difference between the flywheel's lowest and highest reading.

Answer D is wrong. Both Technicians are correct.

Automotive part.

4. The part illustrated above contains:

  • A. A sealed wheel bearing.
  • B. A hub.
  • C. An ABS tone ring.
  • D. All of the above.

4.

Answer A is wrong. All of the above answers are correct. It's a picture of a hub and bearing with an ABS tone ring attached.

Answer B is wrong. The hub in the illustration has a sealed bearing installed.

Answer C is wrong. ABS systems use wheel speed sensors to measure wheel speed with the passing teeth of the attached tone or reluctor ring.

Answer D is correct. They support the vehicle's weight as it accelerates, decelerates, and corners. Many have a wheel speed sensor or its companion tone ring incorporated into their design.

5. A vehicle with a vacuum brake booster and a five-speed manual transmission has a small drip of tan-colored fluid on the driver's side floorboard. Which of the following is MOST likely causing this leak?

  • A. Leaking brake master cylinder cup seals.
  • B. A leaking clutch master cylinder secondary seal.
  • C. A leaking brake vacuum booster check valve.
  • D. A leaking clutch master cylinder primary seal.

5.

Answer A is wrong. A clutch master cylinder uses a single-piston that works similarly to a brake master cylinder. Leaking brake master cylinder cup seals cause the brake pedal to fade to the floorboard.

Answer B is correct. The primary seal leaks internally, and the secondary seal leaks externally. A leaking secondary seal will result in fluid dripping from the clutch master onto the driver's side floor panel.

Answer C is wrong. A leaking brake vacuum booster check valve causes a low source vacuum and a hard brake pedal.

Answer D is wrong. A leaking clutch master cylinder's internal or primary seal results in a loss in pressure and clutch slippage.