Transverse-mounted Manual Transaxle

Manual Transaxle Operation

The manual transaxle: 

  • The purpose of the manual transaxle is to multiply and transmit engine power to the drive wheels of a vehicle.

  • It uses a clutch to disengage the engine from the transaxle, allowing the driver to shift into another gear.

  • The transaxle contains input and output shafts that rotate separately from each other.

  • A countershaft is also used to transfer power between the input and output shafts.

  • Each shaft has helical speed gears that mesh with the countershaft gears for all forward speeds.

  • The reverse gear typically uses a straight-cut spur gear.

  • These shafts and gears work together to let the driver upshift and downshift the transaxle as needed.

Output Shaft

  • The output shaft typically has the pinion gear machined onto its end.

  • It drives the final drive ring gear and differential.

  • The shaft has gears either pressed on or machined into it to transfer rotational power from the speed gears to the input shaft and then to the pinion gear.

  • Two bearings support the output shaft—one at each end.

  • The output shaft shown includes the reverse and fifth speed gears, along with the reverse and fifth synchronizer.

  • It also has two fixed gears called the third and fourth driven gears.

Intermediate Shaft

  • Some transaxles use a third shaft, called the intermediate shaft, to shorten the transaxle and save space for tight operating areas.

  • The transaxle shown includes the first and second speed gears on this shaft, with the 1–2 synchronizer positioned between them.

  • The intermediate shaft also has a fixed gear known as the transfer gear.

Input Shaft

  • The input shaft is splined to the clutch disc and drives all other internal components of the transaxle.

  • It is typically located above the output shaft.

  • Depending on the transaxle design, the tip of the input shaft may use a pilot bearing to support the front of the shaft.

  • A front main bearing supports the load placed on the input shaft from the engine and clutch.

  • The input shaft shown includes the third and fourth speed gears, along with the 3–4 synchronizer.

  • It also has three fixed gears: the first and second input gears, and the fifth drive gear.

Engage the Clutch

  • The driver releases the clutch pedal

  • The release bearing slides back and releases the pressure plate diaphragm spring

  • The engine power is transferred when the clutch makes contact with the pressure plate

Disengage the Clutch

  • The clutch pedal is depressed 

  • The clutch release bearing presses on the diaphragm spring fingers 

  • The fingers act as a lever and pull the pressure plate 

  • The engine power is disconnected