6R80
Major Components
Major Components
For vehicles equipped with a 4.6L or 5.4L engine, this transmission has the following major components:
NOTE: For vehicles equipped with a 6.2L engine, the PCM replaces the Transmission Control Module (TCM).
- Transmission case with integral torque converter housing and extension housing
- Torque converter
- Fluid pump
- Three drive clutches:
- Forward clutch (A)
- Direct clutch (B)
- Overdrive (O/D) clutch (E)
- Two brake clutches:
- Intermediate clutch (C)
- Low/reverse clutch (D)
- Two planetary gearsets:
- Front single planetary gearset (1 sun gear, 1 carrier, 1 ring gear)
- Rear ravigenaux planetary gearset (2 sun gears, 1 carrier with 2 sets of pinion gears and 1 ring gear)
- Main control (mechatronic assembly):
- Upper valve body
- Lower valve body
- TCM
- Transmission Range (TR) sensor
- Turbine Shaft Speed (TSS) sensor
- Output Shaft Speed (OSS) sensor
NOTE: Friction and steel plate quantity will vary based on engine displacement. Refer to the Clutch Plate Quantity Chart in the Specifications.
In addition to the torque converter, the other shift elements are:
- three rotating multi-plate clutches: forward (A), direct (B) and overdrive (E).
- two fixed multi-disc brakes: intermediate (C) and low/reverse (D).
All gear shifts from 1st to 6th or from 6th to 1st are power-on overlapping shifts. That is, during the shift, one of the clutches must continue to transmit the drive at lower main pressure until the other clutch is able to accept the input torque.
The shift elements, clutches or brakes are engaged hydraulically. The transmission fluid pressure builds up between the cylinder and the piston, pressing the clutches together.
The purpose of these shift elements is to carry out in-load shifts with no interruption to traction.
Multi-plate clutches; forward, direct and overdrive, supply power from the engine to the planetary geartrain. Multi-disc brakes, intermediate and low/reverse, press against the transmission housing in order to achieve a torque reaction effect.
Multi-Plate Clutch
Clutches; O/D (E), forward (A) and direct (B) are balanced in terms of dynamic pressure. That is, their pistons are exposed to the transmission fluid flow on both sides, in order to prevent pressure buildup in the clutch as speed increases. This equalization process is achieved by a baffle plate and pressure-free transmission fluid supply by a lubricating passage, through which the space between piston and baffle plate is filled with transmission fluid.
The advantages of this dynamic pressure equalization are:
- reliable clutch engagement and release in all speed ranges.
- improved shift refinement.
Shift Overlap Control
The electro-hydraulic shift action is obtained by means of various valves in the main control valve body, actuated by pressure regulators. They engage or disengage the relevant clutches or brakes at the correct moments.
Hydraulic Systems
Fluid Pump
The torque converter is supported in the fluid pump by a needle roller bearing. The fluid pump is driven directly from the engine by the torque converter shell and supplies transmission fluid to the transmission and the hydraulic control unit.
The fluid pump draws in transmission fluid through a transmission fluid filter and delivers it at high pressure to the main pressure valve in the main control valve body unit. The valve adjusts the pressure and returns excess transmission fluid to the transmission fluid pan.
Fluid Filter
All transmission fluid that is picked up from the transmission fluid pan passes through the transmission fluid filter. The transmission fluid filter and its accompanying seal are part of the transmission fluid path from the pan to the transmission fluid pump.
Single Planetary Gearset
The single planetary gear O/D carrier is driven by the input shaft. The single planetary gear set consists of the following components:
- One sun gear
- Four planetary gears meshing with the sun gear
- One planetary carrier
- One ring gear
Ravigenaux Planetary Gearset
The ravigenaux planetary gearset is splined to the output shaft and consists of the following components:
- Two sun gears of different sizes
- Three short planetary gear pinions meshing with the sun gears
- Three long planetary gear pinions meshing with the sun gears
- One planetary carrier
- One ring gear
Output Shaft
The output shaft provides torque to the driveshaft and rear axle assembly. It is driven by the ring gear of the planetary gearset.
Major Components Cutaway View
Major Components Exploded View
Forward Clutch (A) Plate Quantity
NOTE: The number of clutch plates are model dependant based on engine displacement.
Direct Clutch (B) Plate Quantity
NOTE: The number of clutch plates are model dependant based on engine displacement.
Intermediate Clutch (C) Plate Quantity
NOTE: The number of clutch plates are model dependant based on engine displacement.
Low/Reverse Clutch (D) Plate Quantity
NOTE: The number of clutch plates are model dependant based on engine displacement.
Overdrive (O/D) Clutch (E) Plate Quantity
NOTE: The number of clutch plates are model dependant based on engine displacement.
