One HOT wheel, and three not so hot

Would anyone have a thought on why after driver for a half hour my driver front wheel is 30 degrees warmer than the others? Could it be breaks or a bad HUB?

My first guess would be a caliper that is dragging and not fully releasing pressure on your pads.

Get a cheap infrared thermometer and see what exactly is heating up?

Dragging a pad or stuck caliper for sure I just don't know what the temp difference would be. But when it is it's noticeable that the wheel is hot to touch. Never touch the rotor.

Only thing I can think of is brakes, the LF pads might be not be retracting enough in the caliper. But if that was the case when you hit the brake pedal the truck would veer probably to the left after letting off the brakes. Or the brake hose on the RF side is very restricted. Maybe it got pinched, but more likely that it is swollen on the inside and doesn't let fluid/pressure, equal pressure, go to both front wheels. I know you guys are thinking I'm nuts but a very long time ago I worked on Porsche cars, and my boss would tell me that could happen. Thought he was on drugs but one day a car came in with this type of issue.
How he proved it to me was hit the brakes with the wheels up in the air, depress the brake pedal as hard as you normally would. Then go to the wheels and spin them. In this case one wheel on this car didn't spin as easy as the other side. Loosened the caliper bleeder valve for that wheel and that relieved the pressure from the blockage in the hose to the caliper and the wheel spun freely.

So two possible issues.

Is your raptor stock? Does it pull to one side (steering wheel). Doubtful its a hub, there would probably be some noise contributing to the heat.

First off.

how the hell would you even know that? Has zero symptoms, otherwise you would have said that right?


Because if you are taking a wild guess with your hand, it's exactly that

a wild guess.

It will be the brake caliper. Pull it apart and clean and lube the pins.

I have had to replace hoses that held too much residual pressure on a caliper causing it to drag, always on very old (20+ years) hoses.

The residual pressure for disc brakes is usually 2 psi to keep the piston close to the rotor otherwise the first pump of the brakes will be longer.

I don't know enough about the ABS system and residual valving on our Raptors to diagnose your problem.

Before you replace/rebuild the caliper, try releasing pressure at the bleeder to see if that allows the caliper to retract.

I had a steel belt shift on a tire once, it heated up and ultimately blew out. My only evidence was watching the pressure spike, but thinking it was an anomoly. Maybe, if the above caliper things seem to check out, you rotate the tire and see if the problem moves with the tire, or stays with the driver front suspension.