Exam 9: Torque Converter Principles

Technician A says that some heavy-duty torque converters can be taken apart and rebuilt in a regular transmission repair facility. Technician B says most repair shops exchange torque converters for a remanufactured one. Who is correct?

Technician A says that the torque converter should be replaced when rebuilding a transmission. Technician B says that if a converter is not replaced, it should be checked and flushed. Who is correct?

Technician A says that if loose turbine fins are found, they can be re-brazed to the housing or guide ring. Technician B says that if some fins are damaged, they will be straightened. Who is correct?

Tech A says that the torque converter hub drives the front pump in an automatic transmission. Tech B says that the turbine shaft drives the front pump. Who is correct?

What are the torsional springs in the lockup converter assembly designed to dampen?

Technician A says powertrain mounts hold the engine and transmission in proper position in the vehicle. Technician B says a faulty powertrain mount cannot affect throttle linkage. Who is correct?

Transmission fluid is routed through a heat exchanger in the radiator which keeps the ATF at an ideal temperature: warming the fluid when it is cold and removing heat if it becomes too hot.

Two technicians are discussing transmission heat exchangers. Technician A says when installing an add-on cooler, you should plumb the cooler so the transmission fluid goes through the add-on cooler before the radiator. Technician B says when installing an add-on cooler, you should plum the cooler so the transmission fluid goes through the radiator before the add-on cooler. Who is correct?

Tech A states that lock up torque converters will set a trouble code when they fail. Tech B states that a failed lock up torque converter system may require the rebuild of the transmission. Who is correct?

Technician A says that to properly service a torque converter, it must be cut apart using a special machinist lathe. Technician B says that a serviced torque converter must be welded together then pressure tested for leaks. Who is correct?

Technician A says early torque converters always had some slippage, so in the late 1970's and early 1980's, manufacturers added a lockup clutch to the torque converter. Technician B says typically, torque converter lockup will only happen when the vehicle is under an appropriate load and speed. Who is correct?

Technician A says the transmission should be able to adapt the engine torque to meet the speed and power demands of the vehicle. Technician B says the torque converter does not adapt in this way. Who is correct?

What happens when turbine speed reaches 90% of impeller speed?

Technician A says the stator should be disassembled to test the one-way roller or sprag assembly. Technician B says that each roller should be inspected for scratches or signs of overheating. Who is correct?

When there is a large difference between the speed of the impeller and the turbine:

The torque converter friction material should be inspected and replaced if it shows all of the following EXCEPT:

Two technicians are discussing transmission service on an Allison transmission. Tech A states that the internal filter should be changed every fluid service. Tech B states that the external filter is only changed during the first service. Who is correct?

In a lock-up converter the _______ and _______ are locked together, when conditions are suitable.

Stall is an operating condition where the turbine is stationary and the engine throttle is wide open, making the rotational speed of the impeller as high as possible.

Tech A says that the front pump only operates when the turbine is rotating. Tech B says that a torque converter clutch locks the turbine to the converter housing when applied. Who is correct?