*** Was this grinding present before the caliper replacement or only after replacement?
Is the dust shield rusty, bent, falling apart?
stuck caliper can pulse when they first start....i've heard it before particular if it's the beginnings of being seized due to the swollen pin bushings i'll mention in a moment. it'll get snug, too tight, but not completely seized and the rubber swollen bushings allow some give/play. they will also wear unevenly and the geometry of the pads is affected because it'll be one pin, not both usually.
wheel bearings may be shot but weird for that to happen right when the caliper seized.
(the failing caliper may have previously degraded the already low and aged grease and pushed the bearings to their grave, but that would be uncanny timing)
if you have an infrared temp gun - hit the front wheels with it after the next drive. a failing bearing will generate lots of heat. take multiple measurements on both sides as the variations are wild sometimes before you can see a trend. won't take long to show a huge difference though (high's and lows).
Subaru calipers generally don't need replacing, even here in the rust belt where bolts shear off, we have to drill stuff out regularly, the bleeder screws shear off all the time, caliper slide pins are routinely removed with torches, and brake lines rust through - we have much harsher conditions than you have and even in these conditions i've never seen a Subaru caliper that needed replaced, two that leaked but were rebuildable....it's really rare, so I'd keep my eye out for another cause.
a collapsing brake hose will cause the caliper to seize. but, i'm doubtful as i've never seen it happen in a Subaru. they fail internally and when you press the brakes, they work as normal. but when you let off the brake pedal the hose is collapsed internally and won't allow fluid to back out of the caliper (or does so slowly since there's less hydraulic pressure to return than to brake) or the caliper to back off the rotor....so it acts like a seized caliper. in those cases the brake hose needs replaced and there's no way to really test the hose. i jack the vehicle up and by pressing the brake and letting off you can feel the wheel stop when the pedal is pushed...then still be hard to turn when the pedal is left off. let it sit awhile and it'll spin freely as the pressure slowly bleeds off...repeat to verify collapsed hose.
also - throw the pin bushings away, they are a nightmare. i've seen a bunch of them seize. sometimes right after a brake job...pure speculation that being exposed to new grease or something causes them to swell in the bore and they seize frequently after a brake job. whatever the cause - i see this happen all the time. starts off as light squeaking noises as the rubber bushing is swollen in the bore...then progresses to unevenly warn rotors and loud noises and it gets seized as over time the rubber bushing is smashed into the bore. maybe it's more prevalent here in the rust belt because boots/grease get compromised easier because i don't see many people talking about them but they are a total PITA. it's so common i've been throwing them away for years and I'm all the better for it. older subaru's never had them, there's no symptoms without, so they're not worth my time.
Edited by grossgary, 25 April 2013 - 08:59 AM.