The rotors and pads all look good when checking from under the truck, but I’ve noticed a brake squeak when driving. If I tap the brakes it stops. Caliper piston sticking?
This is what I was initially thinking, and describing, but I don't think so, since the hub seems OK.I should also add that a loose hub will cause the rotor to push the pads and pistons back in the calliper which will require pumping the brakes to regain a firm pedal.
For disk brakes I don't see how that works. When you step on the pedal, the pads are squeezed against the rotor, but when you let up, nothing retracts them (assuming nothing is making the rotor wobble). They just sit there lightly touching the rotor.I've had a few other people step on the pedal to see what they think. Everyone thinks it is extra space between a pad and disk or drum, but I can't see where it is happening.