Brake caliper binding/sticking after hard braking

[Milehighv70xc2]

'99 S70 T5 5spd 206k miles
Front right caliper sticks after hard braking or jamming on the brakes without activating the abs. Doesn't matter if the brakes are cold or hot. ABS does work, I tested it on some ice.
New caliper, even though the old one seemed just fine. Piston retracted with very little effort. Slide pins in good condition and lubed.
Bleed all four corners. Replaced brake line.

Under soft braking it doesn't seem to stick.
After hard braking it sticks bad enough to prevent the car from moving without excessive throttle. After test driving without braking very hard, the right rotor and wheel are much hotter then the other three corners. So it seems the pads are dragging. The car doesnt pull to the right while driving or braking like you would expect from sticking/dragging brake pads.

What could be causing this?
Thanks in advance

[abscate]

I’m going to guess you didn’t spring for Volvo calipers.

The rebuilds are hit and miss. The pistons on the rebuild are pot Metal. It sounds like you have an OBQ, OUT OF BOX QUALITY, part

I feel your pain.

[scot850]

Did you replace the pad guide pins? If they are bad they may be preventing the caliper retract once the pressure is off.

Neil.

[Milehighv70xc2]

Abscate-- New caliper is a Centric rebuild of an OEM caliper. It is stamped Volvo ATE. Centric is a quality brand so its a pretty small chance that it is a bum new caliper. Plus the problem stayed exactly the same.

Scot850-- The guide pins moved smoothly and I regreased them. No signs of corrosion or rust. The piston is in good condition and retracts very easly. So I don't think it is a binding

[wizechatmgr]

When was all the brake fluid flushed out, replaced, and all four corners bled?

[Milehighv70xc2]

All four corners bled was the first thing I did. I have done all this work in the past couple days.

[abscate]

Has the car had a history of 2 year brake fluid changes? It’s rare, but possible, for the master cylinder to develop corrosion with old fluid which can block a port from either delivering or returning fluid to one or more wheel.

The 1999 is a bastard year master cylinder I believe, so watch your part numbers or junkyard picks.

1999-2000 uses 8602305

[Milehighv70xc2]

Abscate- thank you for continuing to help. The fluid was black and looked like used engine oil. I sould have added that in my original post. Not really sure when it was changed last. Atleast 100k on it and probably 10years old. I have been concerned the old fluid did some damage somewhere.

I have been considering the master cylinder. Since there is only two lines coming out of the master, one feeding the front brakes the other feeding the rear, that feed into the abs manifold. Would the problem not effect both front brakes if it where in the master cylinder?

My concern is there is something wrong in the ABS manifold since it is only effecting one brake. Do you guys think maybe there is some corrosion on one of the pintals and it is forcing some fluid into just that caliper with out activating the ABS? Not really sure if that is even possible, I just find it odd only one brake is effected.

Thanks again for all the help

[abscate]

Well , let’s get that old crap out of there and some fresh in. All bets are off corrosion and hydraulics , it could just crap out one wheel.

I’ve had decent luck with Cardone and Centric rebuilds but there is no doubt that rebuild quality is dropping, so don’t rule out a bad caliper OBQ yet. You should be able to return a good caliper piston with finger pressure

[Milehighv70xc2]

Thanks for the quick reply. Bled a bottle and a half through all four corners with no change to the problem. Both calipers, old and new, I could compress with my figures. So I am leaning towards the master I guess.
Seems to be a pretty straight forward replacement... If the lines aren't corroded onto the master. Which I imagine they will be.