Full-time transfer case with synchronized gear reduction unit

摘要

A power transfer system (10) is disclosed for a four-wheel drive vehicle operable for permitting a vehicle operator to select between various full-time and part-time four-wheel drive modes. The power transfer system (10) includes a transfer case (20) equipped with a gear reduction unit (68) and a synchronized range shift mechanism (104) operable for permitting the vehicle operator to shift on-the-fly for establishing full-time and part-time high-range and low-range four-wheel drive modes. The transfer case (20) is also equipped with an electronically-controlled slip limiting/torque-biasing arrangement including an interaxle differential (22) and a transfer clutch (44) operable for controlling the magnitude of speed differentiation and torque biasing across the interaxle differential (22).