Torsion- springs mounted above the door and has cable "drums" on each side
Extension-springs mounted above the track and stretch as the door goes down
For torsion systems. Remove the tension from the springs...loosen each drum. Then starting with the left hand side (if you start at the right your door might sit cock-eyed again), re-wrap the cable around the drum (make sure the cable is taught) and tighten the set screws, then vice the torsion tube or shaft with a vice grip so it will not turn. Then go to the right hand side and repeat the process. Add the tension back to the spring and your door should sit level across the floor.
For Extension springs- just lift your door and re-adjust your springs. (must have the same amount of stretch on the springs when the door is closed).
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