My truck is lowered 3/5 and everytime I hit a good dip or bump my ABS light and parking brake light come on then go right back off and I don't know why.

 

sounds like it could be ground issue. check the grounds on the frame just below the drivers door at the front body mount. i've never heard of them coming on then going out. usually once they come on they stay on.

 

mine has been doing it for years, I thought it was the ABS control module going out. and trust me when those two light come on ABS dose not work. I found out the hard way and it scared the **** out of me.

 

Thanks fellas