Is it bad to drive a thunderbird on the freeway in 2nd gear?

What engine? Driving my Escort at 75mph on the freeway would tach around that normally. I doubt you would do any damage even if it was a V8. I wouldn't do this often as over time it will wear out the engine faster because of the extra stress. John

Which year, which engine? As long as you are below the redline, it should be OK, at least for a short time.