2002 Chevrolet TrailBlazer LS 4WD 4dr SUV (4.2L 6cyl 4A)
Like others, I also have the vibration that occurs around 60mph that can be felt through the accelerator pedal. I brought it in this morning and the service dept. called GM Tech Service. The service consultant told me that GM was aware of this and that it had something to do with the firing impulses. I didn't get into the details. Bottom line, the service dept. couldn't do anything right now but said that hopefully in the near future GM will have a fix.