Description And Operation: GEARTRAIN: Notes

Power is transmitted from the torque converter to the Ravigneaux geartrain components through the input shaft and forward clutch cylinder.

• The geartrain contains a Ravigneaux planetary set connected by dual pinion gears.
• By holding or driving certain components of the gearset, four forward ratios and one reverse ratio are obtained and transmitted to the output shaft.

  The ratios are as follows:

  Fig 1: Identifying Gear Ratio Table

  Courtesy of FORD MOTOR CO.
• Components of the geartrain can be held by bands or clutches and driven by clutches only.

The 4R70W uses:

• two bands.
• two one-way clutches (one roller, one mechanical diode).
• four friction clutches.