ABS braking issues

I have a 2007 Toyota Tacoma 4x4, I got into a rear end accident, new axle, new housing, new leaf springs, new shocks, and bed liner and bedside. I was driving it today and every time it almost get to a complete stop the abs braking would go off. What would make this happen? Also I jus replaced the front passenger side axle. The frame may also be bent. Jus curious on what could be making this happen. And when the front axle broke grease went everywhere, so grease could possible be on the abs sensor could that be a problem as well? Any help will be greatly appreciated!!!! Thanks!!!

 

Sounds like a sensor problem maybe just dirty when you slow down almost to a complete stop and a sensor drops from say 5 mph to zero abs will come on cuz it thinks you are locked up and if it isn't throwing a code you may need a live data scan tool with abs function to read it and see which sensor isn't working right