How to free a stuck brake piston?
July 9, 2008 8:28 PM Subscribe
Car-repair-filter: Any mechanics got a trick for freeing a stuck brake piston?
posted by sergeant sandwich to Travel & Transportation (8 answers total) 1 user marked this as a favorite
So I decide to replace my brake pads this afternoon. I do 3 sets and everything's fine. When I get to the last wheel though, the pads are worn way down, and one of the two pistons on the caliper is funny looking. (I couldn't tell you how it was funny, it just looked odd, for some reason I can't put my finger on.)
Anyway I pull the old pads, grease the shims, slap the new ones in there, and get to the part where you have to push the pistons back into the caliper. The first one went in fine, but the funny-looking one only went in about halfway, and wouldn't go any further.
I tried using a C-clamp and some cardboard to push it in, and opening up the bleeder valve, but the thing still wouldn't budge. So, it's stuck, somehow, probably cocked sideways in its hole. I put the old pads back on (cause the new ones wouldn't fit in the half-open caliper), bled the lines and it drives fine.
I understand that I'm probably looking at doing a caliper rebuild (blahhh), but I'm wondering if there are any trick-up-the-sleeve kind of things that might allow me to free the piston without taking the damned thing apart. If it matters, this is a 1997 Toyota Supra, ABS, two-piston front discs. Thanks!