Question: how to replace a torsion spring?
Answer: Lock down the door. Clamp the door to the track. ...  Unwind the unbroken spring. Use two winding bars. ...  Secure the torsion tube. Use locking pliers. ...  Remove the old spring. Slide the torsion tube over. ...  Buying replacement parts. ...  Install a new center bearing. ...  Thread the cables. ...  Wind the garage door tension springs.