1997 Chevy Silverado Truck won't Move in any gear

Did the trans have an internal failure, cauing it to need a rebuild? In other words, did it blow up before?Sometimes if thetrans cooler isnt flushed out enough or actually replaced in some cases, the material will get into the rebuilt trans and cause another failure. Does the fluid smell burnt?If so this may be asign that it has had a problem for awhile now. Any check engine light? If so, have the PCM scanned to see if mavbe it had a solenoid failure that is keeping it from working. Usually a solenoid issue will at least go into reverse, but you never know. CAll whoever did the trans and have a talk with them. It may be out of warranty, but they should still stand behind their work for more than 21k miles

Does the fluid smell burnt or is it dark in color?If so you may have had another parts failure that has burned up the clutches