don't ask how but I stripped two threads on a rear disc.
So, new discs and bearings installed, old pads. On the passenger side .. inside pad had smaller thickness than outside, compared to the driver side which both were even. Didn't occur to me that might be a problem, put them back on and the passenger wheel was dragging -- the car would pull to the right when not braking. Also, i realized because it was smoking a bit when i pulled over, though the smoke may have been the paint / coating they put on the disc to make it look pretty.
At this point, if i put the parking brake on, it would engage at 2 clicks instead of the normal 5 which i found weird, but that would seem to make sense as the new pads are thicker than the used ones. .
SO, thinking it was the oddly worn pads, i put on my new set of ebc green pads and went around the block trying to bed them in, and now any time I brake with substantial force above 15mph the rear right locks up ... I'm not 100% its the rear right and not both rears ... im not really sure how to check that except have someone watch my wheels when i stop the car.
I should note, when I put the brakes back together after putting the replacement discs, i did not push in the pistons. I'm thinking this has caused a problem and possibly damaged one or both of the rear calipers.
Calipers are low mileage, less than 20k. Carriers slide pins work nicely. If you put the car in the air both rear wheels spin fine. Now, with the new pads, the parking brake is back to the normal 5 clicks i had before. I know it ideally should be adjusted slightly tighter but this is just for reference anyway.
Car is 1995 12v cabrio with corrado front brakes, mk4 aluminum calipers in back. Came with ABS, though I know the wire to the front passenger abs sensor is mangled -- I'm going to fix that wire tomorrow (keep forgetting about it) even though I'm quite sure this is a mechanical problem and nothing to do with ABS (that wire has been mangled for a while and never caused the ABS system to do anything weird).