Garage Door Spring Repair & Replacement in Walnut Creek

Usually runs between $400 to $500 total - that includes parts, labor, and tax. Everything. If you've got two springs, I'm replacing both. If your door only has one spring, it's still in that range. Can't give you an exact price until I see your door (size, weight, what type of springs you need), but that's the typical range.

Don't do it. I'm serious - these springs are under massive tension and can cause severe injury or death if they snap. I've seen guys lose fingers, break arms, and worse.
Plus, if you don't get the spring wound to the right tension, your door won't balance properly and you'll burn out your opener. Just not worth the risk to save a couple hundred bucks.

Yes, always replace both. They've done the same number of cycles - if one broke at, say, 10,000 cycles, the other one's at 10,000 cycles too and about to break.
Plus, if I only replace one, you'll have one new strong spring and one worn-out weak spring trying to work together. That puts stress on your door and opener. Do them both at once, and you're good for another 7-10 years.

Depends on the cycles they're rated for and how often you use your door. If you open your door twice a day, here's roughly what to expect:

■ 10,000-cycle springs: about 7 years
■ 20,000-cycle springs: about 14 years
■ 30,000-cycle springs: about 20 years

Most springs I see fail between 7-10 years. If you're in and out constantly - kids, multiple cars, home business - they'll wear out faster. Just twice a day? They'll last longer.
Extension springs (the ones that stretch along the sides) typically don't last as long as torsion springs (the ones above the door). That's why most newer homes use torsion.