If you have a four wheel drive I suggest first that you go get a owner repair manual but in order to change to four whell drive with a locking hub depending on the vehicle you must turn the metal bar on the center shaft of the wheel hub. that is the locking mechanism. + you may have one or more other things to do so go pay the thirty dollars for the book before you break the front transmission. or wait for a better answer.
The 2003 Toyota Tacoma has rear wheel drive.
The 2006 Toyota Tacoma has rear wheel drive.
The 2002 Toyota Tacoma has rear wheel drive.
The 2014 Toyota Tacoma has rear wheel drive.
The 2004 Toyota Tacoma has rear wheel drive.
The 2010 Toyota Tacoma has rear wheel drive.
The 2005 Toyota Tacoma has rear wheel drive.
The 2007 Toyota Tacoma has rear wheel drive.
The 2013 Toyota Tacoma has rear wheel drive.
The 2008 Toyota Tacoma has rear wheel drive.
The 2009 Toyota Tacoma has rear wheel drive.
The 2011 Toyota Tacoma has rear wheel drive.