Two problems related to brake antilock wheel speed sensor have been reported for the 2001 GMC Safari. The most recently reported issues are listed below.
At slow speeds the abs activates and the vehicle is hard to stop. The sierra van uses the same components as the trucks that were recalled by 05v379000 on 8/3/05. The problem is the same with dirty speed sensors.
I have a 2001 GMC Safari van. Approx 49000 miles. I first expierenced my antiloc brake system activating when not needed at slow speeds. Thinking this was a little odd and I thought I would need to get it to act up more in order to properly explain what is happening to my service personel. And I thought it was minor as even tho the antiloc system activated the brakes seemed to work fine. Untill one day when all I heard was the noise accustomed with the antilock system but the brake pedal went to the floor. After pushing as hard as I have ever pushed on a brake pedal the van stopped. Being afraid to drive it anymore I got it into my service dept. Who replaced both front wheel speed sensors.