A/T System Description - Power Flow

Power Flow (cont'd)


1st Gear

  • Hydraulic pressure is applied to the 1st clutch, then the 1st clutch engages the secondary shaft 1st gear with the secondary shaft.
  • The mainshaft idler gear drives the secondary shaft via the idler shaft idler gear and the secondary shaft idler gear.
  • The secondary shaft 1st gear drives the countershaft 1st gear and the countershaft.
  • Power is transmitted to the final drive gear, which in turn drives the final driven gear and the transfer drive gear.
  • The transfer drive gear drives the transfer drive gear (hypoid gear) and the transfer driven gear shaft (hypoid gear).

NOTE: The illustration shows the 4WD transmission; 2WD does not have the transfer mechanism.

 

2nd Gear

  • Hydraulic pressure is applied to the 2nd clutch, then the 2nd clutch engages the secondary shaft 2nd gear with the secondary shaft.
  • The mainshaft idler gear drives the secondary shaft via the idler shaft idler gear and the secondary shaft idler gear.
  • The secondary shaft 2nd gear drives the countershaft 2nd gear and the countershaft.
  • Power is transmitted to the final drive gear, which in turn drives the final driven gear and the transfer drive gear.
  • The transfer drive gear drives the transfer drive gear (hypoid gear) and the transfer driven gear shaft (hypoid gear).

NOTE: The illustration shows the 4WD transmission; 2WD does not have the transfer mechanism.

 

Power Flow (cont'd)


3rd Gear

  • Hydraulic pressure is applied to the 3rd clutch, then the 3rd clutch engages the mainshaft 3rd gear with the mainshaft.
  • The mainshaft 3rd gear drives the countershaft 3rd gear and the countershaft.
  • Power is transmitted to the final drive gear, which in turn drives the final driven gear and the transfer drive gear.
  • The transfer drive gear drives the transfer drive gear (hypoid gear) and the transfer driven gear shaft (hypoid gear).

NOTE: The illustration shows the 4WD transmission; 2WD does not have the transfer mechanism.

 

4th Gear

  • Hydraulic pressure is applied to the servo valve to engage the reverse selector with the countershaft 4th gear while the shift lever is in the [D], [2], [1] position (forward range).
  • Hydraulic pressure is also applied to the 4th clutch, then the 4th clutch engages the mainshaft 4th gear with the mainshaft.
  • The mainshaft 4th gear drives the countershaft 4th gear and the countershaft.
  • Power is transmitted to the final drive gear, which in turn drives the final driven gear and the transfer drive gear.
  • The transfer drive gear drives the transfer drive gear (hypoid gear) and the transfer driven gear shaft (hypoid gear).

NOTE: The illustration shows the 4WD transmission; 2WD does not have the transfer mechanism.

 

Power Flow (cont'd)


[R] Position

  • Hydraulic pressure is applied to the servo valve to engage the reverse selector with the countershaft reverse gear while the shift lever is in the [R] position.
  • Hydraulic pressure is also applied to the 4th clutch, then the 4th clutch engages the mainshaft reverse gear with the mainshaft.
  • The mainshaft reverse gear drives the countershaft reverse gear via the reverse idler gear.
  • The rotation direction of the countershaft reverse gear is changed by the reverse idler gear.
  • The countershaft reverse gear drives the countershaft via the reverse selector which drives the reverse selector hub.
  • Power is transmitted to the final drive gear, which in turn drives the final driven gear and the transfer drive gear.
  • The transfer drive gear drives the transfer drive gear (hypoid gear) and the transfer driven gear shaft (hypoid gear).

NOTE: The illustration shows 4WD transmission; 2WD does not have the transfer mechanism.