is it a chirp coming from the front wheel? or is coming from the rear?
If it is the front, check your front hubs/wheel bearings for excessive play.
If it is the front check that there is meat left on the pads.
if it is the rear, check wheel bearings for excessive play, as well as drive the truck around for about 20 minutes and see if the brake drums are hot, cold, warm, same or different temperatures.
If you just did the front brakes make sure the metal clip that the brake pads slide on that is located in the caliper mounting bracket is seated correctly and is not making contact with the rotors. In addition to this make sure that the backing plate of the pad is not dangling off and touchng the rotor, or hub area.
More information is needed for a full diagnosis.
2005 Ford Ranger SuperCab XLT 4x4
4.0L V6. 4:10 Gears. BFGoodrich Mud Terrain T/A KM's, Torsion Bar Crank, Bilstein HD Shocks, Autolite Platnium 5143 Plugs, Autolite Professional Wires, Tonneau Cover, Bed Liner, Chrome painted rear differental cover... Thats it.