Red hot rotor

I’ll skip the backstory. Had a caliper not fully release; fortunately on a short drive home from the store. Left rotor was glowing red hot when I got home. [Sadly I didn’t think to get a picture.] Anyway I bought a new caliper, and a new set of rotors and ceramic pads. [Figured it was a good time to get drilled rotors.] Being a 4WD this beast has sealed hub assemblies. They feel smooth enough turning by hand and the vehicle drives okay. My concern is maybe the grease got too hot. The wire coming from the nearby anti-lock sensor does not appear melted or brittle from the heat. The back face of the aluminum wheel does not appear heat-damaged. Question is, should I replace anything else? Does anyone have first-hand experience with a rotor getting that hot?

Make sure the brake hoses to the calipers aren’t deteriorated internally and acting as a check valve keeping the brakes applied.


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Yeah, I think the first thing you need to solve is why the caliper seized up. Otherwise, you’re going to potentially ruin a new set of pads and drilled rotors.

I would suggest replacing both calipers and also agree with Tester and ledhed75’s point about determining why the caliper seized. The piston seized in the caliper bore or the caliper seized on the yoke? Odds are this will happen to the other side at some point and I can’t see ruining new rotors and pads over a lowly caliper.

You should also flush the brake fluid out as much as possible as the fluid is likely cooked and degraded. That can lead to brake fade or worse.

I should have mentioned the truck sat unused for several months and the humidity runs high here in GA. I am confident the caliper was either not freely sliding on its mount, or maybe the piston/seal was offering a little extra restriction. I got it back on the road recently and drove on a few short trips before this happened.

I will clean and grease the right side mount when I go to install the right side rotor.
However with 180K on the clock I suppose new hoses would not be a bed idea in any regard. Also plan to flush the entire brake system. But I think any cooked fluid would have been removed with the old caliper and bleeding the new one.