I just finished rebuilding the left front caliper and replacing the rubber hose, and the inexplicable extra rubber hose on my Intrigue. (Same brakes as GP.) It was hanging up, but not every time I drove it. The wheel would occasionally make some grunting noises and felt a lot hotter than the right front wheel after certain drives.
I wanted to save money, so instead of paying ~$60 for a rebuilt caliper (best I could find from a known brand), I paid $5 for a rebuild kit and $11 for a new piston. (The sticking caliper was a rebuild, just outside the 2-year warranty.) Also, the rotors and pads were still in good shape, so I didn't want a loaded caliper.
Rebuilding was fairly easy, once I got the piston out! After taking the caliper off the rotor, I let the brake system pop the piston out ... but it took a lot of pumping. (I stupidly did this after replacing the hose, when I should have done it first. I had to bleed that corner twice - once to build enough pressure to get the piston out, and once after I got the caliper back together.)
The caliper bore had a thin rust buildup in the area between the piston seal and the dust boot. I don't know if that was enough to cause a sticking caliper, but maybe it could have been. I cleaned it up with a Scotch-brite pad and replaced the seals. I probably could have reused the caliper piston that was in there, but it did show some minor pits, so I used the new one.
I also installed some speed bleeders on both front calipers ($11), so now I have them on all 4 corners. Saves me from looking for a helper.
The hoses were a little difficult to remove, but it worked out okay using a 16mm backup wrench on the female fittings. I replaced the mystery hose with a piece of hard line and a union per the writeup I found on this site:
http://www.grandprixforums.net/5th-brake-hose-hard-line-solution-6-a-6693.html
I regreased the caliper slide bolts, of course. The bolts did not show any wear, which was a good sign, but also suggests that simply regreasing them would not have solved the problem. The boots and bushings seemed okay too, so I left them in place.
Then I bled all 4 brakes, which was pretty quick using the speed bleeders. It was annoying to get to the bleeder screws on the other 3 corners with the wheels installed, but it certainly beats jacking up the car, removing the wheels, and then retorquing them when finished.
Now, all potential problem spots on that corner are fixed, for only about $40. Well, that, and a wickedly painful sunburn. (Oops.)
