My ABS light and alarm sound intermittently while driving highway speeds, I had issues with abs light coming on in January when I was driving in town and coming to a stop. Had front wheel sensors removed and replaced and that fixed problem. Now this!
I posted this question on the GMC forum as well and got pictures along with what to do. The abs ground wire on the back of the motor needs to be moved to the firewall to fix problem. I did that and took for a test drive and abs light and alarm didn't come on.