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Power Flow

Clutches, brakes and freewheel 

Fig 1: Identifying Clutches, Brakes And Freewheel
GLL156326Courtesy of VOLVO CARS CORPORATION
Clutch/Brakes  Function 
Clutch C1 Connects the front planetary gear carrier with the rear planetary train's small sun gear.
Clutch C2 Connects the input shaft with the rear planetary gear carrier.
Clutch C3 Connects the front planetary gear carrier with the rear planetary train's large sun gear.
Brake B1 Locks the rear planetary train's large sun gear.
Brake B2 Locks the rear planetary train's planetary gear carrier.
Freewheel F1 Locks the rear planetary gear carrier so that it does not go counter-clockwise.

Position D, 1st gear 

Fig 2: Identifying Position D For 1st Gear
GLL156327Courtesy of VOLVO CARS CORPORATION
Solenoid  Clutch  Brakes  Freewheel 
SLC1 SLC 2 SLC 3 SLB1 S1 S2 C1 C2 C3 B1 B2 F1
- X X X - - X - - - -* X

X = activated

- = not activated

* B2 is only active during engine braking.

Planetary train unit  Power in  Locked  Power out 
Front Ring gear Sun gear Planetary gear carrier
Rear Small sun gear Planetary gear carrier Ring gear

The input shaft rotates clockwise, the same direction as the torque converter's turbine rotor.

The front planetary train's ring gear rotates clockwise.

The front planetary train's planetary gear rotates clockwise on its shafts. Because the front planetary train's sun gear is locked by the oil pump, the planetary train's planetary gear presses against the front planetary train's ring gear, and therefore rotates around the sun gear. Because the front planetary train's ring gear has inner teeth, the direction of rotation does not change.

The front planetary gear carrier rotates clockwise.

Clutch C1 rotates clockwise and connects the front planetary gear carrier with the rear planetary train's small sun gear.

Rear planetary train's sun gear rotates clockwise.

The rear planetary train's inner planetary gear rotates counter-clockwise on its shaft. The rear planetary gear carrier attempts to rotate counter-clockwise but is prevented by freewheel F1.

The rear planetary train's outer planetary gear rotates clockwise on its shafts. The rear planetary train's small sun gear rotates counter-clockwise, at idle.

The rear planetary train's ring gear rotates clockwise using the rear planetary train's outer planetary gear. Because the rear planetary train's ring gear has inner teeth, the direction of rotation does not change.

The driven gear rotates clockwise. Because the rear planetary train's ring gear is on the driven gear, the driven gear rotates in the same direction as the rear planetary train's ring gear.

The counter-rotating gear rotates counter-clockwise.

The differential's ring gear rotates clockwise.

Position D, 2nd gear 

Fig 3: Identifying Position D For 2nd Gear
GLL156328Courtesy of VOLVO CARS CORPORATION
Solenoid  Clutch  Brakes  Freewheel 
SLC1 SLC 2 SLC 3 SLB1 S1 S2 C1 C2 C3 B1 B2 F1
- X X - - - X - - X - -

X = activated

- = not activated

Planetary train unit  Power in  Locked  Power out 
Front Ring gear Sun gear Planetary gear carrier
Rear Small sun gear Large sun gear Ring gear

The input shaft rotates clockwise, the same direction as the torque converter's turbine rotor.

The front planetary train's ring gear rotates clockwise.

The front planetary train's planetary gear rotates clockwise on its shafts. Because the front planetary train's sun gear is locked by the oil pump, the planetary train's planetary gear presses against the front planetary train's ring gear, and therefore rotates around the sun gear. Because the front planetary train's ring gear has inner teeth, the direction of rotation does not change.

The front planetary gear carrier rotates clockwise.

Clutch C1 rotates clockwise and connects the front planetary gear carrier with the rear planetary train's small sun gear.

Rear planetary train's sun gear rotates clockwise.

The rear planetary train's large sun gear is locked by brake B1.

The rear planetary train's inner planetary gear rotates counter-clockwise on its shaft.

The rear planetary train's outer planetary gear rotates clockwise on its shafts.

The rear planetary train's ring gear rotates clockwise using the rear planetary train's outer planetary gear. Because the rear planetary train's ring gear has inner teeth, the direction of rotation does not change.

The driven gear rotates clockwise. Because the rear planetary train's ring gear is on the driven gear, the driven gear rotates in the same direction as the rear planetary train's ring gear.

The counter-rotating gear rotates counter-clockwise.

The differential's ring gear rotates clockwise.

Engine brake 

When the engine brake works, the driven force is transferred from the tires.

Position D, 3rd gear 

Fig 4: Identifying Position D For 3rd Gear
GLL156329Courtesy of VOLVO CARS CORPORATION
Solenoid  Clutch  Brakes  Freewheel 
SLC1 SLC 2 SLC 3 SLB1 S1 S2 C1 C2 C3 B1 B2 F1
- X - X - - X - X - - -

X = activated

- = not activated

Planetary train unit  Power in  Locked  Power out 
Front Ring gear Sun gear Planetary gear carrier
Rear Small sun gear and large sun gear No component Ring gear

The input shaft rotates clockwise, the same direction as the torque converter's turbine rotor.

The front planetary train's ring gear rotates clockwise.

The front planetary train's planetary gear rotates clockwise on its shafts. Because the front planetary train's sun gear is locked by the oil pump, the planetary train's planetary gear presses against the front planetary train's ring gear, and therefore rotates around the sun gear. Because the front planetary train's ring gear has inner teeth, the direction of rotation does not change.

The front planetary gear carrier rotates clockwise.

Clutch C1 rotates clockwise and connects the front planetary gear carrier with the rear planetary train's small sun gear.

Clutch C3 rotates clockwise and connects the front planetary gear carrier with the rear planetary train's large sun gear.

The rear planetary train rotates clockwise. Because the rear planetary train's inner and outer planetary gears are in constant engagement with each other, they are kinetically locked in relation to each other. The kinetic energy from both the rear planetary train's sun gears is therefore transferred to the rear planetary train's ring gear.

The rear planetary train's ring gear rotates clockwise.

The driven gear rotates clockwise. Because the rear planetary train's ring gear is on the driven gear, the driven gear rotates in the same direction as the rear planetary train's ring gear.

The counter-rotating gear rotates counter-clockwise.

The differential's ring gear rotates clockwise.

Engine brake 

When the engine brake works, the driven force is transferred from the tires.

Position D, 4th gear 

Fig 5: Identifying Position D For 4th Gear
GLL156330Courtesy of VOLVO CARS CORPORATION
Solenoid  Clutch  Brakes  Freewheel 
SLC1 SLC 2 SLC 3 SLB1 S1 S2 C1 C2 C3 B1 B2 F1
- - X X - - X X - - - -

X = activated

- = not activated

Planetary train unit  Power in  Locked  Power out 
Front Ring gear Sun gear Planetary gear carrier
Rear Small sun gear and planetary gear carrier No component Ring gear

The input shaft rotates clockwise, the same direction as the torque converter's turbine rotor.

The front planetary train's ring gear rotates clockwise.

The front planetary train's planetary gear rotates clockwise on its shafts. Because the front planetary train's sun gear is locked by the oil pump, the planetary train's planetary gear presses against the front planetary train's ring gear, and therefore rotates around the sun gear. Because the front planetary train's ring gear has inner teeth, the direction of rotation does not change.

The front planetary gear carrier rotates clockwise.

Clutch C1 rotates clockwise and connects the front planetary gear carrier with the rear planetary train's small sun gear.

The intermediate shaft rotates clockwise, the same direction as the input shaft.

Clutch C2 rotates clockwise.

The rear planetary gear carrier rotates clockwise.

The rear planetary train's inner planetary gear rotates clockwise on its shafts.

The rear planetary train's outer planetary gear rotates counter-clockwise on its shafts.

The rear planetary train's ring gear rotates clockwise. Because the rear planetary train's outer planetary gear rotation pulls away from the rear planetary gear carrier's rotation, the ring gear's speed is lower than the speed at the planetary carrier.

The driven gear rotates clockwise. Because the rear planetary train's ring gear is on the driven gear, the driven gear rotates in the same direction as the rear planetary train's ring gear.

The counter-rotating gear rotates counter-clockwise.

The differential's ring gear rotates clockwise.

Engine brake 

When the engine brake works, the driven force is transferred from the tires.

Position D, 5th gear 

Fig 6: Identifying Position D For 5th Gear
GLL156335Courtesy of VOLVO CARS CORPORATION
Solenoid  Clutch  Brakes  Freewheel 
SLC1 SLC 2 SLC 3 SLB1 S1 S2 C1 C2 C3 B1 B2 F1
X - - X - - - X X - - -

X = activated

- = not activated

Planetary train unit  Power in  Locked  Power out 
Front Ring gear Sun gear Planetary gear carrier
Rear Large sun gear and planetary gear carrier No component Ring gear

The input shaft rotates clockwise, the same direction as the torque converter's turbine rotor.

The front planetary train's ring gear rotates clockwise.

The front planetary train's planetary gear rotates clockwise on its shafts. Because the front planetary train's sun gear is locked by the oil pump, the planetary train's planetary gear presses against the front planetary train's ring gear, and therefore rotates around the sun gear. Because the front planetary train's ring gear has inner teeth, the direction of rotation does not change.

The front planetary gear carrier rotates clockwise.

Clutch C3 rotates clockwise and connects the front planetary gear carrier with the rear planetary train's large sun gear.

The rear planetary train's large sun gear rotated clockwise. Its speed is reduced by the front planetary train so that the speed becomes lower than the speed of the input shaft.

The intermediate shaft rotates clockwise, the same direction as the input shaft.

Clutch C2 rotates clockwise.

The rear planetary gear carrier rotates clockwise.

The rear planetary train's outer planetary gear rotates clockwise. Because the rear planetary gear carrier rotates faster than the rear planetary train's large sun gear, the inner planetary gears are pressed outwards by the speed difference and rotate clockwise on their shafts.

The rear planetary train's ring gear rotates clockwise. Because the rear planetary train's outer planetary gear rotation is added to the rear planetary gear carrier's rotation, the ring gear's speed is greater than the speed at the planetary carrier.

The driven gear rotates clockwise. Because the rear planetary train's ring gear is on the driven gear, the driven gear rotates in the same direction as the rear planetary train's ring gear.

The counter-rotating gear rotates counter-clockwise.

The differential's ring gear rotates clockwise.

Engine brake 

When the engine brake works, the driven force is transferred from the tires.

Position D, 6th gear 

Fig 7: Identifying Position D For 6th Gear
GLL156336Courtesy of VOLVO CARS CORPORATION
Solenoid  Clutch  Brakes  Freewheel 
SLC1 SLC 2 SLC 3 SLB1 S1 S2 C1 C2 C3 B1 B2 F1
X - X - - - - X - X - -

X = activated

- = not activated

Planetary train unit  Power in  Locked  Power out 
Front No component No component No component
Rear Planetary gear carrier Large sun gear Ring gear

The input shaft rotates clockwise, the same direction as the torque converter's turbine rotor.

The intermediate shaft rotates clockwise, the same direction as the torque converter's turbine rotor

Brake B1 locks the rear planetary train's large sun gear.

Clutch C2 connects the intermediate shaft with the rear planetary gear carrier.

The rear planetary gear carrier rotates clockwise.

The rear planetary train's outer planetary gear rotates clockwise on its shafts. Because the rear planetary train's large sun gear is locked, the planetary train's outer planetary gear can always increase the speed.

The rear planetary train's ring gear rotates clockwise. Because the rear planetary train's outer planetary gear rotation is added to the rear planetary gear carrier's rotation, the ring gear's speed is greater than the speed at the planetary carrier.

The driven gear rotates clockwise. Because the rear planetary train's ring gear is on the driven gear, the driven gear rotates in the same direction as the rear planetary train's ring gear.

The counter-rotating gear rotates counter-clockwise.

The differential's ring gear rotates clockwise.

Engine brake 

When the engine brake works, the driven force is transferred from the tires.

Position R, reverse gear 

Fig 8: Identifying Position R For Reverse Gear
GLL156337Courtesy of VOLVO CARS CORPORATION
speed  Solenoid  Clutch  Brakes  Freewheel 
SLC1 SLC 2 SLC 3 SLB1 S1 S2 C1 C2 C3 B1 B2 F1
Max 7 km/h X X X - X - - - X - X -
Above 7 km/h X X X X X - - - - - X -

X = activated

- = not activated

Planetary train unit  Power in  Locked  Power out 
Front Ring gear Sun gear Planetary gear carrier
Rear Large sun gear Planetary gear carrier Ring gear

The input shaft rotates clockwise, the same direction as the torque converter's turbine rotor.

The front planetary train's ring gear rotates clockwise.

The front planetary train's planetary gear rotates clockwise on its shafts. Because the front planetary train's sun gear is locked by the oil pump, the planetary train's planetary gear presses against the front planetary train's ring gear, and therefore rotates around the sun gear. Because the front planetary train's ring gear has inner teeth, the direction of rotation does not change.

The front planetary gear carrier rotates clockwise.

Clutch C3 rotates clockwise and connects the front planetary gear carrier with the rear planetary train's large sun gear.

The rear planetary train's large sun gear rotates clockwise.

Brake B2 locks the rear planetary gear carrier.

The rear planetary train's outer planetary gear rotates counter-clockwise.

The rear planetary train's ring gear rotates counter-clockwise using the rear planetary train's outer planetary gear. Because the rear planetary train's ring gear has inner teeth, the direction of rotation does not change.

The driven gear rotates counter-clockwise. Because the rear planetary train's ring gear is on the driven gear, the driven gear rotates in the same direction as the rear planetary train's ring gear.

The counter-rotating gear rotates clockwise.

The differential's ring gear rotates counter-clockwise.

Engine brake 

When the engine brake works, the driven force is transferred from the tires.