You would think that since gm knows their speedometers have this problem they would issue a recall since it is dangerous but hell, they let people die for yrs with the ignition switch issues before they were forced to recall so i guess i shouldn't be surprised. My sppedo will say 100 mph when im doing apprx 20mph on 1 day and the next day it says I m doing 30 when i am on the freeway passing everyone. i never have any idea how fast im going. It was replaced by previous owner but still has issue and no codes have come up on diagnostics to explain what the problem is so it can be fixed. I have always been a gm girl but they will never get another dime from me! My mechanic told me how much he hates these envoys and trailblazers cuz they caused 1400 of our servicemen to be killed in Iraq and Afghanistan, due to the wiring harnesses that have caused many of the electrical problems these things have. leaving our young men stranded and vulnerable to ambush from rebels which caused so many to be killed, there is a lawsuit before the supreme court now against gm for those 1400 deaths.They continue to ignore the problem and its never been fixed!