ASE ASE Manual Drive Train and Axles 3

Question 1

A FWD vehicle makes a loud clunking noise during acceleration from a stop but not at steady speed. What drivetrain component is MOST likely at fault?

Accepted Answer

Worn or loose inner CV joint

Answer

A clunk under acceleration from a FWD vehicle typically indicates a worn inner CV joint or plunge joint that has excessive play and impacts under torque application.

Question 2

When replacing a CV axle shaft, the technician notices the new boot clamp must be installed in a specific orientation. Why?

Accepted Answer

The clamp must face away from the rotation direction so the lip does not catch and peel back

Answer

Boot clamps must be oriented with their tightening tab trailing (facing away from the direction of rotation) to prevent airflow or road debris from catching the lip and loosening the clamp.

Question 3

A 4WD vehicle with a transfer case makes a grinding noise only when in 4WD high or low but operates quietly in 2WD. What is the MOST likely cause?

Accepted Answer

Worn or damaged transfer case chain or planetary gears

Answer

Noise that occurs only when the transfer case is engaged points to internal transfer case wear, such as a worn drive chain or damaged planetary gears that only carry load in 4WD.

Question 4

A manual transmission pops out of 3rd gear under load. What is the MOST likely cause?

Accepted Answer

Worn or damaged 3rd gear synchronizer hub or detent mechanism

Answer

A transmission that jumps out of gear under load typically has a worn synchronizer hub with rounded engagement teeth or a weak detent that cannot hold the shift rail in position.

Question 5

What is the purpose of checking driveshaft runout and balance?

Accepted Answer

To diagnose vibration caused by a bent or out-of-balance shaft

Answer

Driveshaft runout (measured with a dial indicator) and balance (checked on a balancer) identify bends or mass imbalances that cause vibration at specific vehicle speeds.

ASE - Automotive Service Excellence Certified Tech Practice Test

ASE - Automotive Service Excellence Certified Tech Practice Test

ASE ASE Manual Drive Train and Axles 3