Both calipers have steel pistons and are free. If I open the bleeder, I can easily collapse the caliper pistons.
New hoses and pads.
If the booster was bad, all 4 brakes would drag or lock up.
I loosened the Master from booster and no difference in the drag
What's left? ABS?? What If I remove the ABS fuse? What would happen??
Is it possible that the brake pads can expand when hot? I've never heard of this, but at this point, I'd suspect anything.
Everything that I've researched on the internet, I have checked or replaced.
Buy the way, My truck just turned 35K miles. It is not beaten and kept clean and maintained like all my other vehicles. The truck is a 12 year old new truck. This issue started several years back and has progressively gotten worse. The longer I drive it the more likely the front brakes start to drag. Yesterday after a drive in stop and go traffic for about an hour, the front brakes were steaming hot and smelling. Today, I went out and the front brakes had no drag at all. Seems heat related to me!!!