One problem related to brake electric antilock has been reported for the 2001 GMC C3500. The most recently reported issues are listed below.
Shortly after buying this truck, I was doing less than 20 mph slowing down to stop at a light. I hit a small dump then I heard the abs come on and I roll right through the red light. The dealer told me it must be my driving. After several other similar situations, I had the abs disconected and have not had any other failures.