Book says I have antilock brakes on the back axle, but when I romp on the binders, I get a small (2ft) patch of rubber, then nothing. As expected the front brakes lock up. Any other rig I tried w/ ABS generates a series of short pulses to the brake system. Is this normal behavior for the F350?

 

The rear ABS on my old F-150 behaved the same way as yours. The 4 wheel ABS on the '01 does do the pedal pulsing thing.