If you've researched this subject at all, you will no doubt have heard that you shouldn't be attempting torsion spring replacement as a do-it-yourselfer. That is generally good advice, so if you have any doubts about your abilities to do risky physical work on your own, hire the job out like everyone else. I found I was capable of doing this work with acceptable risk, because I intelligently understood the techniques, paid careful attention to methods and safety, knew how to use common tools in good condition, properly improvised the special tools I didn't have, and diligently attended to correctly performing a few moments of hazardous manipulation. I learned to do it purely on my own based mostly on bits of advice reluctantly given in Internet forums such as the Usenet newsgroup alt.home.repair. When I first wrote this page in 2002, there was no other do-it-yourself information available on the Web, and it was not until 2005 that reliable information disclosing the techniques started to appear elsewhere (see links below).

In this article, we’ll tell you the difference between a safe door and one that’s unsafe. We’ll also give you the helpful tips you’re not likely to find in the manufacturer’s instructions to correctly, and safely, install a new door with a torsion spring and do-it-yourself tensioning. Installing a new, double garage door yourself will save you several hundred dollars and should take eight to 12 hours if you’re fairly handy. You can do most of the project yourself, but you should recruit help for removing the old door.
It’s important to pick a door that suits the style of your house. If you live in a Craftsman bungalow, for example, you might want something that looks like the swing-out doors found on garages behind early Craftsman houses. Manufacturers of modern roll-up doors make them in styles that mimic the old swing doors, complete with faux strap hinges on the sides and a pair of handles flanking a deep groove in the center. 
The Entire job from order through installation was great. The person at Home Depot who helped us made sure we knew exactly what was needed and went over options answering all questions my Fiance had before I could. On install day the installers were not only on time but early which was perfect as i planned my day around them being there and it allowed me to leave a little earlier when they finished to take care of other things. They were polite, knowledgeable, and engaging. Read less
Annual maintenance. Make an annual check of all nuts and bolts on rails and rollers to make sure they’re firmly tightened. Check the condition of all cables to make sure they’re not worn or frayed. Lubricate rollers and springs with a garage-door lubricant (see How to Fix a Noisy Garage Door for maintenance and problem-solving tips). The door should operate smoothly and be properly balanced. Check the balance by disconnecting the opener and lowering the door halfway- the door should hold its position. If it doesn’t, adjust the spring tension or replace the springs.
While winding or unwinding, one must be mindful of the possibility that the spring could break during winding process itself. If that should happen while the spring is significantly torqued, hazardous forces on the winding bar will suddenly become unbalanced, and the bar will take an unexpected jump, possibly injuring your hand or anything else in its path. At the same time, the spring remnants, although captured on the torsion bar, will create a frightening racket that would give the bravest soul a start. So your winding technique should be firmly in control of the rods, and you should not be so delicately perched on a ladder such that a startle will result in a fall.
Door repair business advice (warning to consumers, you are not allowed to know this): Thinner wire is excellent for shortening spring lifetimes, lightening your inventory on a service truck, and getting paid for frequent service calls. This is why your industry chooses to set "standard" springs to have thin wire and despicably short lifetimes. If you want to maximize profits and fleece your customers, install springs that predictably break in about 7 years on a door that should last decades, even though it is just as easy for you to install slightly more expensive springs that should last the life of the door. Remember that the customer wanted the cheapest price, so you need not feel any guilt about this low-balling.
When your garage door starts acting up, more often than not it is telling you it's time to do a bit of maintenance. So, before hitting the panic button, try these simple repairs. First, examine the rollers and tracks. If you can't remember the last time you cleaned them (and they look the part!), give them a good brushing and then add some lubricant. Next, perform these simple garage door maintenance tasks.
Resetting the drums, if needed: If the drums were incorrectly set in their old positions, one must reset both drums in new positions on the shaft. This is complicated by the presence of old dimples in the torsion shaft from previous setting(s), which must be avoided lest they improperly influence the new setting of the drums. To begin this process of resetting the drums, the door must first be lowered and resting level on the floor, the spring(s) must be in the unwound condition with their set-screws loosened, and the lift cables wrapped around the drums. If for some reason the door does not rest level on the floor, such as the floor being uneven, then insert temporary shims between the door bottom and the floor to bring the door up to level. Loosen the set-screws on the drums, and turn the torsion shaft to avoid the old dimples from the set-screws in the old drum position. Tighten the set-screw on the left drum (that is, on your left as you face the door from in the garage), creating a new dimple, and apply tension to its cable with the locking-pliers technique, enough tension to keep the cable taut but not enough to start to move the door up. Attach and wind the cable on the opposite (right) drum by hand until the cable is similarly taut, and set the screw, remembering that tightening the screw will tend to add a bit of extra tension to the cable. Both drums should now be fixed on the torsion shaft, with the cables about equally taut (listen to the sound when you pluck them like a guitar string) and the door still level on the ground. Setting the left drum first, and the right drum second, will allow you to take up any slack in the cable introduced by the left drum rotating slightly with respect to the torsion shaft as you tighten the set screws. This alignment and balance of the cables, drums, and door is critical to smooth operation and proper closing. If you have a single-spring assembly, the distance along the torsion tube from the spring cone to one drum is longer than to the other drum, which allows a bit more twist to one side than the other, and you may have to compensate with the setting of the drums.

Garage Door Service Co