One problem related to transmission stuck in gear has been reported for the 2003 Chevrolet Trailblazer. The most recently reported issues are listed below.
I was driving home to texas from a vacation to visit family in oklahoma. All of a sudden without warning vehicle's transmission got stuck in 3rd gear. Then the transmission failed altogether. Vehicle left me stranded in the middle of nowhere with my four children. They are telling me that there are alot of problems with the Trailblazer transmissions.