3-Speed Shift Sequence

1. 3-Speed Shift Sequence Simpson Geartrain, Tom Birch, 8/06

2. Simpson 3-Speed Transmissions Transmissions that use a Simpson 3-speed geartrain include: DaimlerChrysler: 30RH, 36RH, & 30TH Ford: C4, C5, & C6 General Motors: 3L80/TH 400, 3T40/TH125, TH 200 & TH 350 JATCO: 3N71B Toyota: A40, A41, A131, & A132 Tom Birch, 8/06

3. Neutral Rear Clutch Output Shaft with Ring Gear and Carrier Front Clutch Input Shaft, from Torque Converter Both clutches are released so torque does not get to the planetary gearset. Tom Birch, 8/06

4. Gearset Sun Gear & Shell Front Portion Input/Front Ring Gear Intermediate One-Way Clutch Output/Rear Ring Gear Output/Front Carrier One-Way Clutch Reaction/Rear Carrier Rear Portion Tom Birch, 8/06

5. Gearset 2 Front/Output Front/Input Sun Gear & Rear/Reaction Rear/output Low- Rev. Carrier Ring Gear Drive Shell Carrier Ring Gear Band One-Way Clutch Output Shaft Park Gear & Governor Tom Birch, 8/06

6. Schematic, Gearset Front Ring Gear Torque Converter Rear Ring Gear Output Input Front Carrier Sun Gear Rear Carrier A schematic is the simplest way to show this Torqueflite transmission gear train and its control devices. Tom Birch, 8/06

7. Schematic, Control Devices High-Reverse Clutch Intermediate Band Low-Reverse Band One-Way Clutch Output Input Forward Clutch These are the control devices. They are all released in neutral. Tom Birch, 8/06

8. Hydraulics, Neutral The manual valve limits the paths where hydraulic pressure can flow. Tom Birch, 8/06

9. Shift to Drive Moving the manual valve allows fluid pressure to flow to the 1-2 Shift Valve, Governor, Rear Clutch, and Accumulator. Tom Birch, 8/06

10. 1st Gear, Low Rear Clutch, Applied One-Way Clutch, Holding The rear clutch is applied and driving the front/input ring gear. The one-way clutch is holding the reaction carrier from rotating counterclockwise. The gearset is in a reduction ratio of 2.5:1. Tom Birch, 8/06

11. Gearset Rear Planetary Front Planetary With the vehicle stopped, the front carrier becomes a reaction member, and the front planetary produces a reverse reduction. The rear planetary also produces a reverse reduction, and the two reverses make a forward reduction. Tom Birch, 8/06 Animation: PGS 3

12. Schematic, 1st One-Way Clutch Holding Forward/Rear Clutch Applied A simple view of the 1st gear power flow. Input Reaction Output Tom Birch, 8/06

13. Governor Pressure When the vehicle moves, the governor (arrow) is spun by the output shaft. This moves the governor weights, and generates fluid pressure in the governor passages (orange). Tom Birch, 8/06

14. Shift to 2nd Governor pressure has moved the 1-2 shift valve to upshift. This sends pressure to the front servo to apply the front/ intermediate band. The accumulator strokes to give a smooth shift. Tom Birch, 8/06

15. 2nd Gear, Intermediate Rear Clutch, Applied Intermediate Band, Applied The rear clutch is applied and driving the front/input ring gear. The intermediate band is holding the sun gear from rotating . The gearset is in a reduction ratio of 1.5:1. Tom Birch, 8/06

16. Gearset The rotating ring gear forces the planet gears to walk around the stationary sun gear, and this drives the carrier at a reduced speed. Tom Birch, 8/06 Animation: PGS 3

17. Schematic, 2nd Intermediate Band Applied Forward/Rear Clutch Applied A simple view of the 2nd gear power flow. Input Reaction Output Tom Birch, 8/06

18. Shift to 3rd Increased governor pressure has moved the 2-3 shift valve to upshift. This sends pressure to the front clutch and to the front servo to release the band. Tom Birch, 8/06

19. 3rd Gear, High Rear Clutch, Applied Front Clutch, Applied The rear clutch is applied and driving the front/input ring gear. The front clutch is driving the sun gear. The gearset is locked up in a ratio of 1:1. Tom Birch, 8/06

20. Gearset Driving both the ring and sun gears will lock the gearset in direct drive, a 1:1 ratio. Tom Birch, 8/06 Animation: PGS 7

21. Schematic, 3rd Rear/High-Reverse Clutch Applied Forward/Rear Clutch Applied A simple view of the 3rd gear power flow. Input Reaction Output Tom Birch, 8/06

22. Shift to Reverse Moving the manual valve to reverse allows fluid pressure to flow to the rear servo to apply the rear band and to the front clutch. Tom Birch, 8/06

23. Reverse Rear Band, Applied Front Clutch, Applied The front clutch is driving the sun gear. The rear band is holding the reaction carrier from rotating. The gearset is in a reverse ratio of 2.20:1. Tom Birch, 8/06

24. Gearset The rotating sun gear forces the planet gears to turn the ring gear in a reverse reduction ratio. Tom Birch, 8/06 Animation: PGS 2

25. Schematic, Reverse Rear/High-Reverse Clutch Applied Low-Reverse Band Applied A simple view of the reverse gear power flow. Input Reaction Output Tom Birch, 8/06

26. Variations Center Support/ Low Roller Output Ring Output Input Drum Clutch Housing Clutch Gear Shaft Sun Gear Low & Reverse Clutch Reaction Carrier Some transmissions like the THM 200 use a Low & Reverse clutch to hold the reaction carrier in reverse and manual 1. Tom Birch, 8/06

27. Variations 2 Intermediate Clutch Intermediate One-Way Plates Clutch Direct Clutch Drum Intermediate Band Race Some transmissions like the THM 350 uses an intermediate clutch and one-way clutch to hold the sun gear in 2nd gear. The intermediate band is used in Manual 2nd. Tom Birch, 8/06

28. Variations 3 Low One- Sun Gear Main Input Ring Output Shaft Way Clutch Band Shaft Sun Gear Shaft Gear Reaction Carrier Ring Gear/ Output Carrier The THM 400 has the gearset turned end-for-end so the output ring gear/carrier is connected directly to the output shaft. Tom Birch, 8/06