Look to the right on the panel with the 4wd buttons. It has to have 2 buttons to the far right, one of those will be for the rear locker.
Look closely at this truck, it looks to me like it has "the button":
http://www.carmax.com/enus/view-car...+398+9&Q=07e36ec1-2ed7-4306-b158-4196ea90361e
Look closely at this truck, it looks to me like it has "the button":
http://www.carmax.com/enus/view-car...+398+9&Q=07e36ec1-2ed7-4306-b158-4196ea90361e