ASE A3 Manual Drive Train and Axles

6. The manual transmission's shifter in a light-duty truck feels loose and has excessive play. Which of the following is MOST likely causing this condition?

  • A. A worn shifter bushing.
  • B. A worn detent ball and spring.
  • C. A bent shift rail.
  • D. Bent shift rod linkage.


Answer A is correct. The shift lever bushing is MOST likely at fault. Shifter bushings are plastic bushings and grommets that provide a tight fit and a smooth feel while keeping the shifter firmly in the proper shift rail. View the illustration in the Read more... section.

Answer B is wrong. Shift rails have detent notches machined into their sides. A spring-loaded ball fits into the notch to keep the transmission firmly in gear.

Answer C is wrong. The shift rail should slide easily in its bore and should not have any lateral up and down or side to side movement.

Answer D is wrong. Shift rods are external, and shift rails are inside the transmission. Shift rods require a different type of bushing that provides a tight fit and smooth movement whenever linkage connects.

7. A front-wheel-drive passenger vehicle makes a growling sound that gets louder when turning left. Which of the following is causing this noise?

  • A. A faulty right front wheel bearing.
  • B. A faulty right front outer CV Joint.
  • C. A faulty left front wheel bearing.
  • D. Cupped tire treads.


Answer A is correct. A left-hand turn would reveal a faulty right side bearing because the weight and inertia of the vehicle are pushing on the right front wheel.

Answer B is wrong. A faulty outer CV-Joint typically makes a clicking or clacking sound while slowly turning corners.

Answer C is wrong. A right-hand turn would work the left side wheel bearing because the weight of the vehicle has now shifted to the left wheel.

Answer D is wrong. Both cupped tires and faulty wheel bearings cause a similar growling noise while driving. This problem can make it difficult to distinguish between the two in operation. A cupped tire changes its pitch from one surface to another. This change in pitch is true with all tires, but much more pronounced with a cupped or scalloped tire.

8. A vehicle with a limited-slip differential chatters only while taking turns. Which of the following is causing this condition?

  • A. A worn clutch.
  • B. Using the wrong differential fluid causes chatter.
  • C. Both A and B are correct.
  • D. Neither A or B is correct.


Answer A is wrong. In time, the friction material wears, and the splines and tabs become rounded. Because limited-slip differentials are designed to provide smooth cornering, the symptoms of a worn or damaged differential can become most apparent while taking turns.

Answer B is wrong. Always use the recommended fluid; special limited-slip differential fluid compliments the engagement and release of the limited-slip components.

Answer C is correct. Both A and B are correct. Limited slip differential's lock the two rear wheels together while traveling in a straight line, but allow one wheel to slip while turning. By overcoming the tension of its clutch, the two wheels are allowed to rotate at different speeds during turns.

Answer D is wrong. Use only the manufacturer’s recommended fluid when servicing a limited-slip differential. Servicing with the wrong type of fluid results in vibration and chatter.

9. A high pitched squeal is heard when the clutch pedal is depressed to the floorboard. Technician A says a faulty pilot bearing can result in this condition. Technician B says excessive clutch pedal free travel can cause this squeal. Who is correct?

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


Answer A is correct. A faulty pilot bearing is loudest when the clutch pedal is fully depressed, and the clutch is disengaged. The input shaft and the crankshaft flange are now rotating at different speeds.

Answer B is wrong. Answer A is correct. Excessive clutch pedal free travel results in clutch drag.

Answer C is wrong. The clutch pilot bearing is a ball or roller bearing or a brass bushing that centers the transmission's input shaft in the crankshaft flange.

Answer D is wrong. They produce a squeal or grinding sound when the clutch is disengaged

10. A front-wheel-drive vehicle is being diagnosed for a faulty axle. Technician A says a faulty outboard CV joint makes its most noise while taking turns. Technician B says a faulty inboard CV joint makes its most noise while accelerating and decelerating. Who is correct?

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


Answer A is wrong. They're both correct; a faulty inboard trunion makes a thunking noise while accelerating and decelerating in a straight line.

Answer B is wrong. A worn or faulty outboard CV-joint makes its most noise while cornering. While road testing, listen for a clicking or clacking noise while slowly taking a sharp left or right-hand turn.

Answer C is correct. Both technicians are correct.

Answer D is wrong. Many of these axles have a vibration damper. If the vehicle suffers from front end vibration that's most apparent at higher speeds, inspect the damper.