Abstract: A motor vehicle powertrain includes a transmission producing multiple speed ratios, and a transfer case including a second input driveably connected to the transmission output, a second output continually driveably connected to a first set of wheels and releasably connected to a second set of wheels, for producing alternately in the transfer case a low speed ratio and a high speed ratio. A mode selector produces a signal representing a desired driving mode. A controller, responsive to the signals produced by the mode selector, controls the transmission to produce alternately the multiple speed ratios of the transmission, and for controls the transfer case to operate alternately in the low speed ratio and high speed ratio that corresponds to the desired driving mode and a current speed ratio produced by the transmission.

Abstract: A motor vehicle powertrain includes a transmission producing multiple speed ratios, and a transfer case including a second input driveably connected to the transmission output, a second output continually driveably connected to a first set of wheels and releasably connected to a second set of wheels, for producing alternately in the transfer case a low speed ratio and a high speed ratio. A mode selector produces a signal representing a desired driving mode. A controller, responsive to the signals produced by the mode selector, controls the transmission to produce alternately the multiple speed ratios of the transmission, and for controls the transfer case to operate alternately in the low speed ratio and high speed ratio that corresponds to the desired driving mode and a current speed ratio produced by the transmission.

Abstract: In a motor vehicle driveline having an automatic transmission driveably connected to a transfer case, a park gear, continually driveably connected through a planetary gear set to the drive wheels of the vehicle, is alternately fixed against rotation on the transfer case or released to rotate freely in response to movement of a gear selector having a park position. When the gear selector is moved to the park position, a pawl holds the drive wheels against rotation. When the gear selector is moved from the park position, the drive wheels are free to rotate without restraint of the park mechanism.

Abstract: A four wheel drive vehicle having an automatic transmission and a transfer case. The transfer case includes a planetary gear set and a pair of multi-plate, hydraulically controlled clutches coupled to the gear set for shifting between a high gear ratio and a low gear ratio. The transfer case also includes a four wheel drive, multi-plate, hydraulically controlled clutch coupled to the output of the gear set for switching between a two wheel drive mode and a four wheel drive mode. The hydraulic valving and controls for the hydraulic clutches in the transfer case can be contained in the automatic transmission, with fluid passages to communicate the fluid to the clutches. The planetary gear set in the transfer case can be employed with the planetary gear sets in the transmission to expand the range of output gear ratios from the transfer case.

Abstract: In a motor vehicle driveline having an automatic transmission driveably connected to a transfer case, a park gear, continually driveably connected through a planetary gear set to the drive wheels of the vehicle, is alternately fixed against rotation on the transfer case or released to rotate freely in response to movement of a gear selector having a park position. When the gear selector is moved to the park position, a pawl holds the drive wheels against rotation. When the gear selector is moved from the park position, the drive wheels are free to rotate without restraint of the park mechanism.