ABS Brakes come on

Having trouble diagnosing an ABS brake problem. When slowing down while applying the brakes at about 4 miles per hour the ABS kicks in and the vehicle keeps going. It seems that when you try locking the brakes up from say 30 miles per hour it releases for a second. When you slow gentley from say 10 miles per hour with light brake pressure the ABS works (releases) for 5+ seconds. The ABS light does not come on so it doesn throw a code. I have an actron scanner with ABS and it shows no codes. I found some problems with the adjusters in the rear so I replaced them along with the hardware to make the work corectley. Fluid was low and I topped it off.
Another thing I found odd was that I could power brake the vehicle. I found no recall from ford motors, but this is a definate safety issue.