We had a Garage Torsion Spring that had snapped (Made in Canada..eh). Went ahead and picked up a new spring at Overhead Door Professional Services Inc. Warning, this is a dangerous job and precaucions should be taken if you decide to do this yourself. Of course you could just have Overhead do the job for you, or could ignore all of that noise put some thick long sleeves on, safety glasses and de-pansy yourself while also saving $200 plus. To start unbolt the wheel and bracket at one side while leaving the other side bolted. Unbolt the spring and slide it off. Slide the new one back on, bolt it up and then bolt the wheel back and tighten the braided cable. Clamp some vice grips on the shaft so it doesn't move and start tightening the spring with a bar found at any local hardware stores. Keep tightening and adjust as necessary until the garage lifts easily and until your automatic opener can open and close at ease. This is the dangerous part. If something snaps or isn't tight when carefully winding this spring it could snap which could pop your shoulder out, take out some fingers or something might fly back towards your head. Stay Safe.