[Shotimes] SHO brake drag--nothing has helped yet (sort of long, but crucial to resolve)

[Jim Koper]

This may be somewhat long, but hopefully a thorough description will help
develop an accurate solution.

My left front brake is dragging--it smells like it! It feels hotter, too.
Over the course of several months I replaced the obvious: the flex hose (the
old one was ballooning); the caliper--twice (free LTW replacement, Warner
brand); slider pins (first set looked dried out, most recent set was dried
out and rusty, so I reconditioned with emery paper); bled the brakes again.

Brake is still dragging. PFCM pads show even wear from side-to-side and
front-to-rear. A little white residue on pads due to the sticking and
resulting heat transfer.

What are the chances of getting two defective calipers in a row (purchased
8+ months apart)?

I've used synthetic caliper grease (blue stuff) and then tried wheel bearing
grease as slider pin lubricant. Both seem to dry up prematurely--the pins
rarely come out 'wet with grease.'  I was very surprised at the rust this
time, but even after reconditioning with emery and regreasing the pins, the
brake still drags. Any other suggestions for pin lube?

Could the (original) master cylinder be defective? It passes the "lift the
pedal with your toe" test with no signs of sinking.
While the pedal is firm while braking, I notice at stop lights that, with my
foot on the brake pedal, it will sink slowly, perhaps an inch or two. If I
lift off the pedal and pump it again, it firms up again. Is THIS a sign of a
defective power booster or an internal leak? Is there a test that I or the
(shudder!) dealer can do to rule out replacing the master cylinder? Wouldn't
the brakes drag on all four corners if the MC were bad? High speed stops and
normal braking are not a problem, so I doubt if it's a matter of some air in
the system.

ANY possibility that the wheel bearing might be going out and THAT is what
is causing the sticking--and maybe that's what I am smelling? I don't hear
the 'traditional' parking lot slow-turning noises at all, though there seems
to be a slight play in the tire (the "12 and 6 o' clock"  test). This
dragging has been going on for 1+ years, so I figure a bad wheel bearing
would have gone out LONG ago....

ANY chance that the spindle / hub might be bent a bit, causing binding for
the caliper assembly?

Feel free to chime in. I am open to everyone's experience and advice on
this. I'm at my wits end and about ready to replace all four calipers, pins,
flex hoses, and e-brake cables (need those anyway) AND the master cylinder,
if that what it takes. (I'd hate to spend all that time and money and still
have the problem..)

Thanks in advance!

Jim Koper
1992 red on black
151,000 miles