A transfer case of a motor vehicle drivetrain includes a planetary gear set including a ring gear to receive input torque, and a pinion assembly having pinion gears in mesh with the ring gear and a carrier to carry the pinion gears and transmit output torque. A sun gear is in mesh with the pinion gears, is selectively connectable to the carrier and rotatable therewith in a two-wheel drive mode and in a four-wheel-drive high range mode, and is selectively fixable against rotational motion in a four-wheel drive low range mode.