'87 240; after sitting in the garage for a few days, I had the car out and it was pulling to the right on my way to school yesterday. When I left school to go to NYC, it was fine, but on the highway, the steering wheel started to shake and I could smell burning brake lining. I pumped the brakes a few times and it went away for awhile, but came back again after I exited some toll booths. I repeated the brake pumping action, and the shimmy disappeared for the rest of my trip into the city and then back home (about a one hour highway drive home). I am hoping there is a possibility that some dirt or debris jammed up in the caliper and then went away when I pumped the brakes the second time.
Should I consider replacing both front calipers, or is it possibly just a matter of lubricating the slides? What about "boiling" the brake fluid?
The car stops in a straight line and still felt fine today when I took it to work.
--
http://www.facebook.com/album.php?aid=53563&id=1189132524&l=75a2564d60

I've had this happen solely due to rust in the ways. The pad gets jammed up in the swollen caliper, yet the pistons are able to retract. This is just one way it can happen. This is the time of year for that around here.
--
Art Benstein near Baltimore

When tempted to fight fire with fire, remember that the Fire Department usually uses water.

I'd just lever the pistons in and press them out again a few times, and make sure that they move freely. In my experience they are often prone to sticking, more usually being sluggish to engage rather bthan release.