Noticed that the brake pedal went to the floor

F150 OWNER

MEMBER
1998 FORD F-150

A couple of months ago, I replace the calipers and pads on the front of my F150. I notice that the truck seemed to be dragging and that the front rims were really warm. Someone suggested that I should replace the short brake lines that connect the medal tubing to the calipers, which I did. At that point I started to bleed the system (with the car running) and noticed that the brake pedal went to the floor, but I tried to bleed the system with no change. When the truck is off you can pump the brake and it firms up a little. After talking to the parts guy, he stated that it was the Brake Cylinder. So with a little help and bench bleeding the new Brake Cylinder, I put it on the truck only to find that it didn't fix the issue. Now some people say it might be the Brake Booster! Please help!

1 Reply

SQM

MECHANIC
6,383 POSTS

Hello,

There could few different reasons why the pedal is going to the floor.
It could be from air in the line, weak master cylinder, bad brake booster, also for having a leak anywhere in the brake system.

Take a look at this article, it covers all the common causes and remedies:

https://www.2carpros.com/articles/brake-pedal-goes-to-the-floor

Typically, if the brake can be pumped up when the engine is off but losses pressure after startup, it is a vacuum issue on the brake booster.

I have attached the general brake diagnostics below.

Please let me know of any questions.
Thank you.

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