In-Vehicle Maintenance and Repair Flashcards

After a transmission range sensor is replaced, the engine cranks in Neutral but not in Park. Which is the most likely cause?

Answer: The range sensor is not aligned with the manual shaft

Park and Neutral should both close the start circuit. If only Neutral does, the sensor's alignment with the manual shaft is off.

ATF is seeping from the lower bell housing inspection area, and the back of the engine is dry. The fluid is red and the leak is at the torque converter hub. Which seal is most likely leaking?

Answer: Transmission front pump seal

ATF at the converter hub points to the front pump (converter hub) seal. The rear main seal would leak engine oil.

When reinstalling a transmission pan with a new gasket, which procedure best prevents leaks and a warped pan flange?

Answer: Tighten the bolts in a crisscross pattern to the specified torque in stages

Staged, crisscross tightening to the specified low torque, usually in inch-pounds, gives even clamping. It avoids crushing the gasket or distorting the pan.

The ATF on the dipstick is milky pink and the cooling system level is dropping. The transmission cooler is inside the radiator tank. What is the most likely cause?

Answer: A leak between the cooler and coolant passages in the radiator

Coolant and ATF mixing through a failed radiator-tank cooler gives pink, milky fluid and a falling coolant level.

A vehicle clunks and the engine visibly rocks each time the shifter is moved from Park to Drive. The transmission shifts normally otherwise. Which component should be inspected first?

Answer: Powertrain mounts

Excessive engine movement at engagement points to worn or broken engine or transmission mounts.

A new valve body is being installed. The bolts are of several lengths. What is the correct practice?

Answer: Install each bolt in its matching location and tighten in the specified sequence and torque

Valve body bolts differ in length and must go in their original locations, tightened to the specified low torque and sequence.

A scan tool shows the transmission range sensor reading Drive while the shifter is in Park. The shift cable was recently adjusted. What should the technician do first?

Answer: Verify the shift cable adjustment, then align the sensor to the manual shaft per specification

A disagreement between the shifter and the sensor usually means linkage or sensor alignment, so check those before replacing parts.

A technician is checking the fluid level on a transmission without a dipstick. Which procedure is correct?

Answer: Bring the fluid to the specified temperature with the vehicle level, then check at the level plug as directed

Sealed units are checked through a check plug at a specified fluid temperature, usually read with a scan tool, with the vehicle level.

ATF is leaking at the output shaft seal on a rear-wheel-drive transmission, and the seal looks worn on one side. What else should be checked and likely replaced?

Answer: The extension housing bushing

A worn extension housing bushing lets the yoke move off-center, which wears the seal unevenly and makes it leak again.

A transmission that recently had a major internal failure is being fitted with a replacement unit. What should be done to the external cooler and lines?

Answer: Flush and flow-test them per the manufacturer, and replace the cooler if it cannot be cleaned

Debris trapped in the cooler can destroy the new unit, so the cooler must be flushed and flow-tested or replaced.

While draining the pan on a high-mileage transmission, a technician finds bronze-colored particles on the pan magnet. What do they most likely indicate?

Answer: Worn bushings or thrust washers

Bronze or brass-colored particles point to worn bushings or thrust washers, which are made of those materials.