2002 chevy trailblazer 4wd ltz

That would be my first thought. Check the shift control solinoid.

Did some one tell you it was a good trany? If so, was the torque converter installed properly? Did you use your old torque converter, or one that came with the other trany? Is the shift linkage hooked up right? Shift threw the gears while adding trany fluid so the oil circulates? Other than these things, you may have to dig deeper.

thanks for ur response but i got it the speed sensor wires were tore of the harnes and i put them back and it worked perfect thanks thoe

Always something hey...

where is the speed sensor wires that broke

sorry but it was the the shift solenoids but now im having other problems with it