ABS activativing only below 5mph, on dry pavement

2000 Chevy Silverado, I can stop from 80 to Zero with no problems. If I go from 10 mph and then try to stop, the brake pedal seizes at 5 mph, it feels like the abs has activated but the truck will not stop, and a noise comes from the L wheel area. If the brake is released and pushed again the truck stops normally. The noise is not metal on metal, but more like the noise that the abs makes upon activation. The brakes have been replaced, we replaced the abs unit, but the problem continues. There is no noise during normal driving, or stopping until the speed gets to 5 mph. No noise during turns, and the wheel doesn’t have any shake in it when I test for bearing problems. The problem was intermittent, but no is continuous.

The problem may be caused from this condition. http://www.justanswer.com/questions/13me7-proper-procedure-troubleshooting

Tester