One problem related to speed control cable has been reported for the 2005 Chevrolet Trailblazer. The most recently reported issues are listed below.
Driving on the highway to the shore my speedometer increased to 95 mph. When we parked it was stuck on 10. Since then it has happened many times. When I park I have to check what it stops at. Sometimes, its 10, 20, 30, etc. I have tried disconnecting the negative battery cable and that helps as a temp fix. My dealer says there is no recall, but I saw online a class action suit against gm, but not for Trailblazers. This is a gm issue and I don't have the money to get it fixed. Updated 03/11/14.