98 Corolla, 346K original miles
Notice uneven hot rotors and mushy brake pedal. No problem – time for a brake overhaul. Replaced rotors, pads, calipers (front original), drums + shoes in the rear, bled all lines with fresh DOT3-- still sticky calipers (esp on driver side) and mushy pedal. Thinking defective new calipers, replace again – same. What could this be?
Front rubber brake hoses look fine (never clamped during all DIY brake work), but decided to swap these before considering replacing the master cylinder. Messy job. Bled the front lines. What a difference!
Solid pedal, firm easy stops. The low brake pedal is also fixed – the degradation over 19 years has been so subtle that I did not even notice that the pedal was low. Apparently internal rubber deterioration was closing the ID of the rubber hose and restricting flow, especially in the unloaded low pressure direction (released pedal). Dragging pads gone – can actually feel better off the line acceleration. Slight increase in gas mileage.
Lesson: replace the caliper brake hoses regularly