2003 f150 2wd, this started about a week ago;
when braking the pedal feels fine then will drop just a little and then feels fine again, kinda like air is in the system, but it's not.
Brakes only have 15,000 mi front and 5,000 rear. had brake fluid changed at dealer couple days ago thinking that old fluid or air was the culprit but nothing has changed. when truck is stopped at idle the pedal has no fade at all and when truck is cut off the pedal hardens up like its supposed to, any body have any ideas???? much appreciated.

 

booster maybe? anybody have an idea??

 

I would guess it would point more towards the master cylinder than the booster. Typically you have a hard pedal when you have problems with the booster.

 

replaced pads, hardware, and rotors again, that fixed it. not sure what the exact culprit was, but evetything works correctly now.

 

Glad you got it fixed, but damn that's not a cheap way to do it. Anyways, glad all is good now. Just curious did you go with the same or different parts the second go around? Can you list out what you used?

 

Thanks,
I only replaced the front brakes. All the new parts from autozone this time, solid rotors,ceramic pads, same as rear. Last set on front was an internet order.
The inside pad on the front driver side was wearing very uneven, like it was getting "hung up" and not sliding smoothly in the caliper. Just changed the pads and hardware first and that fixed the soft pedal for the most part but the rotors didn't feel right so I swapped them out too. $125 rotors, $55 pads, $15 hardware kit.
Still cheaper than taking it to the dealer and letting them solve the mystery.