2005 F150 Brakes

[CadCruzer]

I think I have brake master cylinder that is going bad. The symptoms are. When the brake pedal is pushed with a firm and steady presure the pedal will go to the floor. also alldata says you should see a surging/bubbling in the resorvor when the pedal is pushed and released, I see nothing. If I give the pedal a quick push then apply the brakes the pedal is firm.

As always, Thanks for your input

[Jeremy airjer W]

That is certainly a common symptom however if it is equipped with rear drum brakes I would certainly take the time to check too see if the wheel cylinders are leaking and/or the adjustment on the rears is correct.

If the master cylinder is determined to be the cause go with a new unit not a rebuilt. The new units are generally much better. The remanufactured ones always seem to have problems included the same problem you have described. Its a little more for new but the time you save in possible having to do the job more than once is priceless!!

[Scott K]

Before condeming the master cylinder, what is the complaint with the brakes? On almost all new Fords I can push the pedal to the floor if I want to. If your concern is that you have a low pedal, did you just put new brake pads on, sometimes it takes awhile to break in! If the concern is that sitting at a stop sign with a normal pressure on the brake pedal, you notice the truck wants to start rolling unless you apply more pressure, then its a possible master. I havent replaced to many master cylenders on the newer body style trucks so far!