Geartrain

Power is transmitted from the torque converter to the Ravigneaux geartrain components through the input shaft and forward clutch cylinder.
- The geartrain contains a compound planetary set connected by dual pinion gears.





- By holding or driving certain members of the gear set, four forward ratios and one reverse ratio are obtained and transmitted to the output shaft.

The ratios are as follows:
- Members of the geartrain are held by bands and driven by clutches.

The 4R70W uses:
- two bands.
- two one-way roller clutches.
- four friction clutches.

PLANETARY GEAR SET
The planetary gear set in the transmission is a Ravigneaux-type set consisting of the following components:
- Forward clutch sun gear
- Reverse clutch sun gear
- A pinion carrier
- Long and short pinions
- Output ring gear

Members are held or driven to produce forward and reverse gear ratios.

INPUT SHAFT
The forward clutch cylinder and shaft transfers speed and torque from the converter turbine to the geartrain. This shaft is splined to the turbine on one end and to the forward clutch sun gear and input shaft on the other end.

STUB SHAFT
The stub shaft transfers power from the turbine shaft to the planet carrier (through the direct clutch) during third and fourth gear operation.

OUTPUT SHAFT
The output shaft provides torque to the driveshaft and rear axle assembly. It is driven by the ring gear of the planetary gear set.