From the Wikipedia article:
So it seems the Explorer had this system (or at least a direct predecessor) two years before the VX went into production in Japan.ControlTrac four-wheel drive is the brand name of a selectable automatic four-wheel drive system offered by Ford Motor Company. The four-wheel drive system was designed and developed at BorgWarner under its TorqTransfer Systems division in the mid 1980s.[1][2][3] BorgWarner calls the system Torque-On-Demand (TOD).
Vehicles available with automatic ControlTrac four-wheel drive
Vehicle Model Year Transfer case
Ford Explorer MY1995-2010 two-speed