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Power Flow

When throttling off, the output shaft's power in 5th, 4th, 3rd, 2nd or reverse gear goes directly to the input shaft without any freewheel, which provides engine braking. 1st gear does not have any engine braking since the power transmission is interrupted by freewheel.

Position 

Fig 1: Identifying Power Flow Position P
GLL140682Courtesy of VOLVO CARS CORPORATION

Primary shaft 

The input shaft rotates clockwise. All clutches and brakes are disengaged, and no power is transferred to the planetary trains.

Output shaft 

No power is transmitted to the output shaft. Brake band locks the sun gear so that it cannot rotate in any direction. Shiftlock, which is affected by the mechanical link system, is engaged with the lock wheel on the output shaft and prevents the vehicle from rolling.

Position 

Fig 2: Identifying Output Shaft Position N
GLL140683Courtesy of VOLVO CARS CORPORATION

Primary shaft 

The input shaft rotates clockwise. All clutches and brakes are disengaged, and no power is transferred to the planetary trains.

Output shaft 

No power is transmitted to the output shaft. Brake band locks the sun gear so that it cannot rotate in any direction. Shift-lock is disengaged. The planetary gears can rotate freely around the sun gear and the vehicle will start to roll if it is on an incline.

The reason for the brake being activated in both as -position is to minimize the engagement shock that otherwise is produced when several brakes and clutches are activated at the same time when the gear selector is moved to or -position. Since is still activated in both first gear and reverse, in this way simultaneous engagements are reduced.

Position and 1st gear 

Fig 3: Identifying Output Shaft Position D And 1st Gear
GLL140684Courtesy of VOLVO CARS CORPORATION

Main section 

The input shaft rotates clockwise. Clutch connects the input shaft to the rear ring gear, which rotates clockwise. The rear planetary gear rotates clockwise. The front large planetary gear rotates clockwise with the rear planetary gear as a unit.

The front small planetary gear rotates clockwise. The front ring gear rotates counter-clockwise. Freewheel locks the front ring gear's rotation counter-clockwise.

The front and rear planetary carriers are turned clockwise because of the reactive forces from the small gear. The primary intermediate gear rotates clockwise with the front and rear planetary carriers as a unit.

U/D section 

The secondary intermediate gear rotates counter-clockwise. The front ring gear rotates counter-clockwise with secondary intermediate gear as a unit.

The front planetary gear rotates clockwise. The front planetary gear rotates clockwise. The rear sun gear rotates clockwise with the front sun gear as a unit.

The rear planetary gear rotates counter-clockwise. Brake locks the rear planetary carrier's rotation. The rear ring gear rotates counter-clockwise. The front planetary carrier and final drive pinion rotates counter-clockwise with the rear ring gear as a unit. The final drive rotates clockwise.

Engine brake 

The primary intermediate gear and front and rear main planetary carriers rotate clockwise. The rear planetary carrier rotates clockwise. The rear planetary gear is turned counter-clockwise while it rotates counter-clockwise because of the resistance from the rear ring gear.

The front large gear wheel is turned clockwise while it rotates counter-clockwise and the small gear wheel is turned clockwise while it rotates clockwise. The front planetary carrier is turned clockwise.

The front ring gear rotates clockwise because the front small gear rotates clockwise, but drive force is reduced because freewheel is disengaged. Therefore the engine brake does not operate.

Position and 2nd gear 

Fig 4: Engine Brake Position D And 2nd Gear
GLL140685Courtesy of VOLVO CARS CORPORATION

Main section 

The input shaft rotates clockwise. Clutch connects the input shaft to the rear ring gear. The rear ring gear rotates clockwise. The rear planetary gear rotates clockwise.

The front large planetary gear rotates clockwise with the rear planetary gear as a unit. Brake, freewheel and brake lock the sun gear's rotation.

The front and rear planetary carriers are turned clockwise because of the reactive forces from the front large gear. The primary intermediate gear rotates clockwise with the front and rear planetary carriers as a unit.

U/D section 

The secondary intermediate gear rotates counter-clockwise. The front ring gear rotates counter-clockwise with the secondary intermediate gear as a unit. The front planetary gear rotates clockwise. The front planetary gear rotates clockwise.

The rear sun gear rotates clockwise with the front sun gear as a unit. The rear planetary gear rotates counter-clockwise. Brake locks the rear planetary carrier's rotation. The rear ring gear rotates counter-clockwise.

The front planetary carrier and final drive pinion rotates clockwise with the rear ring gear as a unit. The final drive rotates clockwise.

Engine brake 

Drive force is transferred directly to the input shaft without the one way clutch. Therefore the engine brake operates.

Position and 3rd gear 

Fig 5: Engine Brake Position D And 3rd Gear
GLL140686Courtesy of VOLVO CARS CORPORATION

Main section 

The input shaft rotates clockwise. Clutch connects the input shaft to the rear ring gear. The rear ring gear rotates clockwise. The rear planetary gear rotates clockwise.

The front large planetary gear rotates clockwise with the rear planetary gear as a unit. Brake, freewheel and brake lock the sun gear's rotation.

The front and rear planetary carriers are turned clockwise because of the reactive forces from the front large gear. The primary intermediate gear rotates clockwise with the front and rear planetary carriers as a unit.

U/D section 

The secondary intermediate gear rotates counter-clockwise. The front ring gear rotates counter-clockwise with the secondary intermediate gear as a unit. The front planetary gear rotates clockwise. Brake locks the rotation of the front and rear sun gear.

The front planetary carrier is turned clockwise because of the reactive forces from the front large planetary gear. The front planetary carrier and final drive pinion rotate clockwise with the rear ring gear as a unit. The final drive rotates clockwise.

Engine brake 

Drive force is transferred directly to the input shaft without the one way clutch. Therefore the engine brake operates

Position and 4th gear 

Fig 6: Engine Brake Position D And 4th Gear
GLL140687Courtesy of VOLVO CARS CORPORATION

Main section 

The input shaft rotates clockwise. Clutch connects the input shaft to the rear ring gear. The rear ring gear rotates clockwise. The rear planetary gear rotates clockwise.

The front large planetary gear rotates clockwise with the rear planetary gear as a unit. Brake, freewheel and brake lock the sun gear's rotation.

The front and rear planetary carriers are turned clockwise because of the reactive forces from the front large gear. The primary intermediate gear rotates clockwise with the front and rear planetary carriers as a unit.

U/D section 

The secondary intermediate gear rotates clockwise. The front ring gear rotates counter-clockwise with the secondary intermediate gear as a unit. Clutch C3 connects the sun gear to the front planetary carrier.

The front planetary gear cannot rotate and the U/D unit rotates counter-clockwise as a unit. The final drive pinion rotates counter-clockwise with the U/D unit as a unit. The final drive rotates clockwise.

Engine brake 

Drive force is transferred directly to the input shaft without the one way clutch. Therefore the engine brake operates.

Position and 5th gear 

Fig 7: Engine Brake Position D And 5th Gear
GLL140688Courtesy of VOLVO CARS CORPORATION

Main section 

The input shaft rotates clockwise. Clutch connects the input shaft to the rear ring gear. Clutch connects the input shaft to the sun gear.

The rear planetary gear cannot rotate and the rear planetary gear unit rotates clockwise as a unit. The front planetary gear cannot rotate with the rear planetary gear as a unit. The front planetary unit rotates clockwise as a unit. The primary intermediate gear rotates clockwise with the front planetary unit as a unit.

U/D section 

The secondary intermediate gear rotates counter-clockwise. The front ring gear rotates counter-clockwise with the secondary intermediate gear as a unit. Clutch connects the sun gear to the front planetary carrier.

The front planetary gear cannot rotate and the U/D unit rotates counter-clockwise as a unit. The final drive pinion rotates counter-clockwise with the U/D unit as a unit. The final drive rotates clockwise.

Engine brake 

Drive force is transferred directly to the input shaft without the one way clutch. Therefore the engine brake operates.

Position 

Fig 8: Engine Brake Position R
GLL140689Courtesy of VOLVO CARS CORPORATION

Main section 

The input shaft rotates clockwise. Clutch connects the input shaft to the sun gear. The sun gear rotates clockwise.

The rear planetary gear rotates counter-clockwise. The front large planetary gear rotates counter-clockwise with the rear planetary gear as a unit. The front small planetary gear rotates clockwise.

Brake locks the front ring gear's rotation counter-clockwise. The front and rear planetary carriers are turned clockwise because of the reaction forces from the front small gear. The primary intermediate gear rotates counter-clockwise with the front and rear planetary carriers as a unit.

U/D section 

The secondary intermediate gear rotates clockwise. The front ring gear rotates clockwise with the secondary intermediate gear as a unit. The front planetary gear rotates clockwise. The front sun gear rotates counter-clockwise.

The rear sun gear rotates counter-clockwise with the front sun gear as a unit. The rear planetary gear rotates clockwise. Brake locks the rear planetary carrier's rotation. The rear ring gear rotates clockwise. The front planetary carrier and final drive pinion rotate clockwise with the rear ring gear as a unit. The final drive rotates counter-clockwise.

Engine brake 

Drive force is transferred directly to the input shaft without the one way clutch. Therefore the engine brake operates.