I recently bought a 2005 F-150 with the 5.4L engine and the factory tow
package.  This is probably a dumb question but I can't figure out if it
has a controller for electric trailer brakes or not.  The
light/electrical connector at the hitch has the pins for it.  Do I need
to buy/install a controller, or is one built in?

This is important because I am about to buy a large travel trailer and
it's a long drive home (about 16 hours) from where I will pick up the
trailer, so I need the brakes to be working when I hit the road!  I
could call the dealership and ask, but I don't really trust them.  They
told me my towing capacity was 9500 pounds, but in fact it is only 8000
(based on engine, rear axle ratio, and 18" tires).

Any help appreciated!