Toyota Repair: Bleed brakes, freeway miles, rear brakes

Question
I have a 2002 4x2 4Runner automatic with 55k freeway miles.  The brakes feel spongy.  I took out the pads and compared it to a set of new pads and it has about 90% left.  Do I need to bleed the brakes so it wont be so soft?  If so, how do I do that?

Answer
Air normally doesn't enter the hydraulic system unless there is a hydraulic fluid leak in the system, somehow I don't think this is the case here, the vehicle is too new to be having this kind of problem, so I don't think it is the problem.Before you do anything and possibly waste your time and money, adjust the rear brakes, out of adjustment rear brakes will cause a low and spongy pedal.