Two things. First, the doors I have are getting little flecks of rust from grinding metal and the sparks hitting the doors, plus they are getting dirty from years of my greasy hand on them. Just finished redoing all the trim on the front of the garage because apparently carpenter ants really like the taste of that finger jointing wooden trim. Now the trim looks great and the doors look like crap. Whats the best way to go about painting them again? Am I just better off buying new doors? They are aluminum clad, textured, raised panel doors and are 5 sections each. I say take them off, power wash them, wipe them down with prep sol, sit them on saw horses and spray them with rustoleum or even brush paint them with rustoleum. Second. Went to get the TR8 out of the garage yesterday and the door wouldn't budge. Went inside to inspect and on one side the lifting spring snapped. Force generated by the recoiling spring took out the angle iron drop for the rear most section of the track. Just did a little reconnaissance over on the big box store website. Figured springs were just sold by length, but they are pretty much a standard length with different spring rates. How do I know which one to buy short of removing a panel and weighing it, which I might be doing anyway??? Is there some secret stamp on the spring or on the door panels that have a weight rating that only the thieving garage door specialists know about?
I painted mine with exterior Behr paint from HD, its been 5 years and they still look great.
Regarding the springs, I always thought the different rates had a different color painted on them. But not 100% sure.
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I suggest checking with local garage door companies to see what they would charge to replace the spring. It's not that hard to do yourself if you're careful, but they can do it very quickly and it's not all that expensive. One of the springs broke on my door a few years ago, and since it was -20F that week I hired out the job; the repair guy had the new spring installed in about 20 minutes flat.
Steel clad insulated garage doors are so cheap I wouldn't even waste a gallon of paint. New rails, new wheels, springs, hinges...
Just be a bit cautious with the springs when you replace them. Lot of stored energy there that could leave a mark on you if things go awry.
I replaced the springs on one of my doors last year, it's not hard. First, they are color coded. Look for a splash or spray near one end. Be sure to get a pair and make sure the colors match!
Second, the pull type springs are NOT under tension when the door is rolled all the way up. The twist type which go around the bar are still under tension when the door is all the way up, so with those proceed with extreme caution. The door still needs to be all the way up when replacing those, BTW.
Once the door is all the way up, make note of which holes the pull type spring is mounted in. It might help to use a Sharpie to mark the holes. Tension springs also typically have a safety cable run through the middle, you'll need to unhook that. Then disconnect the spring ends and slide it off the cable. Typically you'll need to be ready to hold the spring and idler wheel up during installation, might need Vise Grips etc to do that. Put the safety cable through the spring, then installation is the reverse of removal. 
If yours has the twist type springs, you are best off to find the manual to determine how to release the preload. Hot tip: I've used a cordless drill with a hex bit to back the tension off, but beware; the gears are typically plastic. Turning them at high speeds can overheat the plastic, meaning accidental release of spring preload. Not a good idea.
Ive noticed some repainted doors tend to stick to the vinyl trim making them hard to open, while others dont. Something to investigate before choosing a paint, if you choose to go that route.
On the spring, if they're all the same length and diameter and different rates, I imagine the variable is the wire diameter.
In reply to gearheadmb:
Latex paint will do that.
Wife and I managed to get the door lifted up and I shoved a piece of gas pipe in the track to hold it up. Now I can back the 8 out and hit the cruise night at the local Wally world tonight. The door is 9X8, and even with one spring, it was heavy. I took down the broken spring. Its covered in rust. I'll take it with me to the Depot tonight and try and match it up. Probably going to replace the ones on the other door while I'm at it. There is a lift just in back of that door with 2 of my nicer TR8s stacked one over the other. A broken spring on that side could do some serious damage. If you lift the door all the way up, the springs are no longer in tension. Take out a bolt thru the pulley and the the spring falls right into your lap. Thanks for all the warnings for my safety, but I built the garage and installed the doors 15 years ago, so no worries there.
Run a piece of cable through the center of the new springs to contain them if they ever do break.
