Cadillac Repair: Brakes, cadillac seville sts, 1994 cadillac seville sts

Question
Doing a brake job. 1994 Cadillac Seville STS w/ABS Replaced rotors, calipers & pads.  R.R. brake was dragging.  Tore up pads & the rotor.  Now, I find that after bleeding, and applying brakes, the R.R. does not release until I open the bleeder valve.  All other wheels release.  

Have checked the line and hose and all seem in working order.  Could I have an ABS system problem here?

Thanks for any help...

Larry

Answer
Sounds like the caliper is distorted internally via the rubber seals have gotten hard due to the heat and will not allow the piston to retract.

However, IF each rear wheel have it's own rubber brake hose going to the caliper the rubber hose needs to be replaced as it has hardened internally due to the heat from your problem.