Transaxle Description
Transaxle Description
This DPS6 is a fully automatic, dry dual clutch, automatic shifting manual, electronically controlled 6-speed transaxle.
Its abbreviated designation DPS6 means:
- D- Dry Dual Clutch
- P- Powershift
- S- Synchronized
- 6- 6-speed transaxle
This transaxle features the following:
- Computer Control with electro-mechanical actuation
- Two piece aluminum housing design
- Six (6) discrete stepped forward gears and one (1) reverse gear
- Dual Output shafts with two separate final drive ratios
- Full ball and roller bearing design for all gears and shafts
- All gears are bevel cut for improved NVH characteristics and power transfer
- All gears are in constant mesh for no loss of torque during the shifting process
- All cast construction of shift fork/linkage mechanisms
This transaxle features two nested input shafts driven by a compact dry dual clutch system. These two shafts are used in conjunction with each other to provide seamless shifting through the six (6) available ratios with overdrive in the two top gears. As each gear is selected, the appropriate clutch is activated to drive the vehicle. Each consecutive gear is then preselected for the next "shift" operation as power is shifted from one clutch to the other and back again as moving up and down through the individual gears
This transaxle is designed to be operated in the same manner as a conventional torque converter equipped automatic transaxle. It provides the smooth application of power, but with the bonus of efficiencies found only in a manual transaxle. By delivering the power with a dual clutch system, fluid volume is limited to less than 2 liters as compared against a conventional automatic transaxle, and that is only within the gearbox case itself. The actuation of the clutch system is controlled by a dedicated computer through two individual electrically driven clutch motors and actuator systems.
This transaxle provides six (6) discrete forward ratios with overdrive in the top two gears and a reverse gear, giving a continuous flow of power for acceleration and deceleration
The selector lever gives the driver a choice of P, R, N, D and L.
With the selector lever in the D position, you can operate the Transmission Control Switch (TCS) /Grade Assist switch on the selector lever to prevent the transaxle from shifting into 6th gear.
If a fault occurs continued motoring is guaranteed in the following limited conditions based on the failure: 1st, 3rd and 5th gear if a fault with clutch 2 and/or relational components occurs. 2nd, 4th, 6th and reverse if a fault with clutch 1 and/or relational components occurs.
This transaxle can be tested using a scan tool through the Data Link Connector (DLC) in the passenger compartment.
Internal components are based on manual transaxle technologies that include:
- Dry friction clutches to transmit power between the engine and transaxle
- Lay shaft gearing for high efficiency and uncoupled ratio selection
- Rotating sequential shift drums for fast response
- Synchronizers with dog clutches to pre-select and direct the power flow
- Splash fluid lubrication without filter and external oil coolers
This transaxle is two transaxles within one housing that share a common:
- Final drive which includes two output shaft pinions
- Differential assembly
- Output Shaft Speed (OSS) sensor
- Transmission Range (TR) sensor
- Park system
- Transmission Control Module (TCM)
The first consists of three odd gear ratios (1st, 3rd & 5th):
- Odd input clutch and actuator system including a clutch motor
- Odd or inner input shaft with input shaft speed sensor 1 and related speed gears
- Odd synchronizer system including a shift motor (part of TCM (Transmission Control Module)), shift drum, shift forks and transfer assemblies.
The second consists of three even gear ratios and reverse (2nd, 4th, 6th & Reverse):
- Even input clutch and actuator system including a clutch motor
- Outer or hollow input shaft with input shaft speed sensor 2 and related speed gears.
- Even synchronizer system including a shift motor (part of TCM (Transmission Control Module)), shift drum, shift forks and transfer assemblies
1st Gear
The torque is introduced into the dual clutch via the flywheel. From there, the power is transmitted via clutch 1 to the inner input shaft. The inner input shaft transmits the torque to the first gear of the output shaft. The torque is transmitted to the differential via the output pinion.
2nd Gear
The torque is introduced into the dual clutch via the flywheel. From there, the power is transmitted via clutch 2 to the hollow input shaft. The inner input shaft transmits the torque to the second gear of the output shaft. The torque is transmitted to the differential via the output pinion.
3rd Gear
The torque is introduced into the dual clutch via the flywheel. From there, the power is transmitted via clutch 1 to the inner input shaft. The inner input shaft transmits the torque to the third gear of the output shaft. The torque is transmitted to the differential via the output pinion.
4th Gear
The torque is introduced into the dual clutch via the flywheel. From there, the power is transmitted via clutch 2 to the hollow input shaft. The hollow input shaft transmits the torque to the fourth gear of the output shaft. The torque is transmitted to the differential via the output pinion.
5th Gear
The torque is introduced into the dual clutch via the flywheel. From there, the power is transmitted via clutch 1 to the inner input shaft. The inner input shaft transmits the torque to the fifth gear of the output shaft. The torque is transmitted to the differential via the output pinion.
6th Gear
The torque is introduced into the dual clutch via the flywheel. From there, the power is transmitted via clutch 2 to the hollow input shaft. The hollow input shaft transmits the torque to the sixth gear of the output shaft. The torque is transmitted to the differential via the output pinion.
Reverse
The torque is introduced into the dual clutch via the flywheel. From there, the power is transmitted via clutch 2 to the hollow input shaft. The hollow input shaft now transmits the torque to the reverse/2nd double gear which acts as an idler gear to reverse the direction of rotation. This idler transmits torque to the reverse gear of the output shaft. The torque is transmitted to the differential via the output pinion.