Newb - 3/13/2012 7:39 PM

I am a newb to fishing and boat towing.... well towing anything in general. Just a quick question... on my shifter there is a button I can push in. It has a towing icon that comes up on the dashboard. What exactly does hitting this button do, does it put the truck into a different mode? Also, when should I be using this? Should I use it whenever I am towing, just while towing on the free way, just off the free way? Like I said I am new to this and hopefully someone can help me out.....