Update on the brake situation: It was a wheel cylinder.
Asking the obvious, have you checked the wheel cylinders?
On both wheel cylinders the pistons toward the front of the truck where seized. I guess I didn't realize this because both sides where acting the same but only one side was getting hot. That and I suck at troubleshooting
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I guess the one brake shoe was stuck dragging just enough to cause the heat but not enough to cause any real drag on the wheel.
I did leave the washers on that Liveoak suggested. I'll keep an eye on things to make sure the brakes continue to self adjust correctly.
Aisin/Advics wheel cylinders
7/8" 4cyl WCT-007
15/16" V6 WCT-027
1" FJ60 WCT-011
I went with the 7/8" cylinders for now. I need to upgrade my booster and then the rest of the system.