Transaxle Operation

TRANSAXLE OPERATION





The following conditions apply when the input shaft only is moving (no clutches applied):
- 4th drive and 4th driven gears moving.
- All remaining gears including the differential are stationary.
- Output shaft is stationary.
- Input shaft moving over caged bearings and case bearings.

The following conditions apply when the output shaft is moving:
- 1st drive and 1st driven gears moving.
- 2nd drive and 2nd driven gears moving.
- 3rd drive and 3rd driven gears moving.
- 4th drive and 4th driven gears moving.
- Differential is moving.
- Reverse drive and reverse driven gears moving.
- Reverse idler gear moving.

COLD TEMPERATURE OPERATION - Under cold operating conditions the high viscosity of Automatic Transaxle Fluid (ATF) can result in sluggish operation of the hydraulic controls of the automatic transaxle. Because of this, when the transaxle fluid temperature is below -13°C (9°F) the PCM will control the transaxle using only 1st and 3rd gears. Once the transaxle fluid temperature is above - 12°C (10°F), the PCM will control the transaxle using the standard shift patterns.
Saturn exclusive features are as follows:
1. Uphill Feature - while traveling up certain grade hills, the transaxle will not upshift to a higher gear if that gear cannot maintain speed on the grade. Even if a driver completely lifts off the throttle, the transaxle will not upshift thus preventing unnecessary shifting. After reaching the top of the hill, the normal gear shift schedule will resume operation.
2. Downhill Feature - If traveling down steep grades, the PCM may automatically select a lower gear. This system assists engine braking, reduces transaxle shifting, and reduces braking required while going down a hill.
3. Traction Control - Under certain slip conditions, the PCM may perform an upshift to help reduce slip.