2004 GMC ENVOY User Comment / Complaint

I just bought a used 04 gmc envoy with 30,000 miles on it. now about a month after i bought it i'm having problems with the speedometer. sometimes it works sometimes it doesn't. when it does not work it reads to high or two low. i can be driving down the road at 65 and it will drop below 0. or i can be stopped at a light and it shows 40. a quick search on the web shows thousands of people with the same problem. i feel gm and gmc should have to do a recall on this as it could be a life and safety item. for example one could slow to the recommend speed for a curve or a turn. if the speedometer is reading two low then the person would be traveling two fast for the turn. i see also where a class action law suit is in the works on this.