I have an 04 F150 STX 2wd, 4.6L, auto, 77,000 miles. During braking, and just before the truck comes to a full stop, the brakes start pulsating like the ABS is detecting a skid. The pedal gets hard and braking effectiveness is reduced. Sometimes the ABS light comes on, but resets when I turn the key off. Brakes seem to work normally at all other speeds...this only happens at very low speed. I can pull the ABS fuse disabling the system and the problem goes away, but I lose ABS and the yellow ABS caution light stays on.