I'm a newbie here , please don't hurt me . '03 Ranger 4wd , When the brakes are applied all is well until just before the truck stops , then the brakes pedal sinks a little , gets soft , there is a soft thunk sound and it feels like the brakes have quit . Then a slight clicking and a breath taking moment of free wheeling before the truck stops . Is there a sensor on each wheel that can be R&R ed ? How do I examine the sensors to find the bad one(s)? Are the brake sensors the problem ? Any help would be tremendous . Many thanks. Ditgramps.