Rear Brake sticking after brake pad change

[SolidLifter]

Hi, I have a 1994 Q45a with 135,800. I have had the car since it had about 65,000 miles, Never changed the rear pads, because they were in good shape. Two weeks ago, I heard them squealing and decided to change all 4 (Front and rear). After installation I did not brake them in properly, but didn't think much of it. The next day, I noticed the rear brakes were sticking and the car was dragging heavily. Brake pedal felt like crap, mushy, rubbery, the whole lot and car would not stop like it used too.
The rears were heating up badly. I thought it was the centric pads I installed, so I installed a new set (different brand) with all new shims, bled the brakes and took it for a test drive. After about 5 miles they were sticking again. So now i changed the calipers on both sides. Bled the brakes again, flushed the old brake fluid out. The brake pedal now feels much better, but the rears are still sticking. Not as bad, but they are. Does anyone have a clue as what might be the issue. The hoses look ok, based on visual and flow coming out of the bleeder screw. Does the q45a, have a different type of pads. The only thing I noticed was that the old calipers I took off, didn't look OE to me. They weren't sumitomo. If anyone has any clue as what might be the cause, please let me know. I hate driving around town, feeling like I am towing 15,000 lbs.

[Q451990]

Is it possible that the sticking is coming from your emergency brake shoes instead of the pads?

[3Q Jay]

caliper pins binding?
the left rear on my 94 active did this periodically, think it was a worn caliper piston.

[3Q Jay]

oh, almost forgot! Make sure you have a 'solid' buzz-thunk at 3mph from the ABS self test. I also ended up replacing an ABS relay (near firewall) on the '94.