Kia Optima Hybrid Owner's Manual Quiz
Automatic Transmission

Flow Diagram

In this manual: Automatic Transmission
General Information — 4Engine Mechanical System — 50Engine Electrical System — 20Emission Control System — 30Engine Control System/Fuel System — 84Automatic Transmission — 98Drive Shaft and Axle — 15Suspension System — 36Steering — 12Restraints — 50Brake System — 38Body (Interior and Exterior) — 54Body Electrical System — 233Heating, Ventilation, and Air Conditioning — 57
~4min read

Power Flow Diagram

P, N UD/B LR/B 26/B 35R/S OP/K OWC E/C
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? Direction of rotation: Activation of low and reverse brake (LR/B) > Overdrive (O/D) hub lock > Middle and rear lock P/C ? Input shaft rotation > Rear sun gear rotation > Rear internal gear rotation (reverse) > Rear external gear rotation > Reverse ring gear rotation > Front ring gear rotation > Front gear rotation > Front sun gear rotation (reverse) > Underdrive (U/D) hub rotation (reverse) ? Input shaft rotation > Overdrive clutch (OD/C) retainer rotation ? Input shaft rotation > 35R clutch rotation
R UD/B LR/B 26/B 35R/S OP/K OWC E/C
? ? ? ? ? ?

Power Delivery Route: Center planetary carrier locked, center sun gear rotates. Rotation of the center planetary sun gear while the carrier is fixed in place slows and rotates the ring gear in reverse (front carrier), transmitting power to the front carrier. The rear and front ring gears of the rear planetary gear rotate at reduced speed, resulting in reverse rotation without load on the front sun gear of the front planetary gear.
D1 UD/B LR/B 26/B 35R/S OP/K OWC E/C
? ? ? ? ? ?

? Power delivery route ? Front sun gear, middle and rear carrier are locked, and rear sun gear rotates continuously. ? When the rear sun gear rotates, power is reduced at the rear planetary gear set and then delivered to the rear and front ring gears. Power is then reduced again at the front planetary gear set, whose sun gear is fixed in place, and then delivered to the front carrier. ? Here the middle ring gear, integrated with the front carrier, rotates and drives in reverse, with zero load on the middle sun gear rotation.
D2 UD/B LR/B 26/B 35R/S OP/K OWC E/C
? ? ? ? ? ?

? Power delivery route ? Front sun gear and middle sun gear are locked, and rear sun gear rotates continuously. ? Rotation of the rear sun gear transmits power to the rear and front ring gears, and the reaction of the front carrier and middle ring gear, to which the sun gear is attached, transfers to the middle and rear carriers, resulting in power balance and power transmission to the front carrier.
D3 UD/B LR/B 26/B 35R/S OP/K OWC E/C
? ? ? ? ? ?

Power Flow Path — Front sun gear is locked, and the center and rear sun gears rotate. Rotation of the center sun gear and rear sun gear transmits power to the rear and front ring gears, and the reaction from the front carrier and center ring gear, to which the sun gear is attached, transfers to the center and rear carriers, resulting in power balance and power transmission to the front carrier.
D4 UD/B LR/B 26/B 35R/S OP/K OWC E/C
? ? ? ? ? ?

? Power delivery route ? Front sun gear is locked, and rear carrier and rear sun gear rotate. ? Activation of the overdrive clutch (OD/C) synchronizes the rear planetary carrier and sun gears. A 1:1 rotation ratio passes through the rear and front ring gears and reaches the front planetary carrier, to which the sun gear is attached. ? Here the middle sun gear of the middle planetary gear set rotates at higher speed in the normal direction, with zero load, due to the reduced ring gear and carrier having a 1:1 rotation ratio.
D5 UD/B LR/B 26/B 35R/S OP/K OWC E/C
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Power Flow Path — Center and rear carriers, center sun gear and rear sun gear are rotating. The center carrier and center planetary sun gear rotate simultaneously, resulting in a 1:1 rotation ratio transmitted to the center ring gear (front carrier). Here, the rear planetary gear set rotates at a 1:1 gear ratio, as in 4th gear engagement; however, the front planetary gear set remains unlocked, and the front sun gear rotates in the normal direction at zero load and a 1:1 gear ratio.
D6 UD/B LR/B 26/B 35R/S OP/K OWC E/C
? ? ? ? ? ? ?

? Power delivery route ? Middle carrier rotates, middle sun gear is locked ? When the middle planetary sun gear is locked in place and the middle carrier is allowed to rotate, the middle ring gear increases rotation speed and transmits power to the front carrier. ? Here the rear planetary gear set maintains a 1:1 rotation ratio, as in 4th or 5th gear; however, the front planetary gear set remains unlocked, and the front sun gear rotates faster in the normal direction with zero load. ? Engine clutch (E/C) Engine clutch (E/C) is released in EV mode. In HEV mode and engine-drive mode, the engine clutch (E/C) is engaged, connecting engine power to the automatic transmission.
Mode EV HEV Engine Only
Engine Clutch (E/C) ? ? ?

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