03 f150 brake problems., brakes stop good the petal go to floor.


Asked by Jan 13, 2017 at 12:52 PM about the 2003 Ford F-150 XL Extended Cab SB

Question type: Maintenance & Repair

Repair center said master cyl. replaced 3 times, new pads on rear and bled them out,  lines and calipers work as should , now wants to replace the valve up front on drivers side where the lines run to at 1100 and 50 dollars with no guarantee ,  thoughts please.  can't afford that.

12 Answers


I think you need another mechanic.


He didn't bleed then enough, I still think you have allot of air in the system...

Best Answer Mark helpful

Forgot no brake light on and when it goes to the floor it sound like air escaping


If, when you picked up the car, the brakes were good, then began going to the floor, you're getting air into the system at some point. Check the level of the brake fluid and see if you are loosing any.


Never lost any break fluid even on the original master cyl. the brakes won't right when i picked it up. the service center said he did not know what else to do and i needed to get another opinion on it. he wanted to try a 1100 dollar fix without knowing what wrong.


The brake pedal going to the floor indicates a few possibilities. There is air in the system. Air is compressible resulting in the pedal going to the floor. The other possibility is that the piston inside the master cylinder is allowing brake fluid to pass by the seal when the pedal is pushed. This happening on more than one new cylinder is remote. Question: Each time you received the vehicle back from the service center, was the brake pedal acting as it should? Or was it "to the floor" right out of the center?


There is another remote possibility. When a master cylinder is removed you will see a short shaft sticking out from the booster with a screw inserted into the end. This is an adjustment for the travel of the pedal prior to the piston being pushed and applying pressure to the brake system. If this screw got turned inward (somehow), making the distance from the head of the screw further away from the piston, then the pedal would have to be travel further before contact was made with the piston and applying pressure to the system.

1 of 1 people found this helpful.

AS i stated before the brakes stop the truck fine .it is when it is stopped that the brakes start to ease all the way to the floor. you can let the brake petal back up and it holds a few seconds then ease to floo r again.

1 of 1 people found this helpful.

This is the reason i took it to start with.


OK, the pedal holds, but slowly goes to the floor. Here are two possibilities. There is an internal leak within the master cylinder. There are two sets of seals on the piston. When pushed the fluid stops the vehicle but the fluid is being pushed past the seal backward toward the booster. Since the master cylinder has been changed this could be the problem, but the original problem is why you brought it to the shop in the first place, right? If the master cylinder has been changed more than once I doubt this is the problem. Second. One of the seals is bad within a caliper. Since the seals suppose to hold hydraulic pressure, it will hold in the fluid, but it maybe sucking air when the pedal is released. Try bleeding your own brakes. If there is air in the system at any wheel check all hoses for cracks. This is going to be a process of elimination one wheel at a time working back to the master cylinder.

Needs a HCM . Hydraulic Control module . All so know as ABS Module . It has a internal leak.

I have the same problem .... my mechanic said its most likely the ABS module ..... very expensive part , like $ 1000 from ford .... he tries to get a second hand unit for about half .... has had to fix a bunch of them .... mine is a 2003 with 234 k on it .

Your Answer


Looking for a Used F-150 in your area?

CarGurus has 9,917 nationwide F-150 listings starting at $3,490.

Postal Code:

Ford F-150 Experts

  • #1
  • #2
  • #3
View All

Related Models For Sale

Used Chevrolet Silverado 1500
156 Great Deals out of 12,235 listings starting at $1,895
Used GMC Sierra 1500
172 Great Deals out of 12,023 listings starting at $1,775
Used Ford F-250 Super Duty
21 Great Deals out of 765 listings starting at $3,500
Used Toyota Tundra
49 Great Deals out of 1,553 listings starting at $5,999
Used Dodge Ram 1500
49 Great Deals out of 483 listings starting at $2,495
Used Toyota Tacoma
32 Great Deals out of 1,353 listings starting at $6,900
Used Ford Mustang
1,030 listings starting at $3,900
Used Ford F-350 Super Duty
28 Great Deals out of 1,367 listings starting at $8,777
Used Chevrolet Colorado
30 Great Deals out of 2,781 listings starting at $3,980
Used Chevrolet Silverado 2500HD
14 Great Deals out of 1,468 listings starting at $3,300
Used Nissan Titan
31 Great Deals out of 744 listings starting at $2,322
Used Ford Explorer
35 Great Deals out of 1,602 listings starting at $4,500
Used Chevrolet Tahoe
3 Great Deals out of 913 listings starting at $9,871

Used Cars For Sale

2018 Ford F-150 For Sale
8 Great Deals out of 5,326 listings starting at $26,750
2017 Ford F-150 For Sale
57 Great Deals out of 854 listings starting at $24,100
2016 Ford F-150 For Sale
70 Great Deals out of 855 listings starting at $21,996
2015 Ford F-150 For Sale
114 Great Deals out of 678 listings starting at $19,995
2014 Ford F-150 For Sale
81 Great Deals out of 514 listings starting at $9,995

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.