I have a 97 f150 2wd. The brakes worked fine before my grandfather blew a line just before i bought it from him. I repaired the line and bled the brakes, a half dozen times, still soft pedal.

I read some forums and decided to replace the master cylinder, rubber lines and all the older rusted lines. Bled it a few more times after that and still have a soft pedal that goes almost to the floor.

I've changed lines and bled brakes on multiple vehicles and never had a problem, I'm stumped.

If anyone has an idea the info would be greatly appreciated, I really don't want to pay for the dealer to fix it. lol.

 

Does this truck have rear drum brakes? If so, they could be way out of adjustment.

Also, I have seen this issue on GM vehicles that have been run dry of brake fluid. The fix was to actuate the ABS module (to remove air) during a special brake bleed procedure with a GM scan tool. Not sure if Ford is the same or not.

Good luck!

 

Not sure about how to fix this but my 06 has the same issue. Plus my brake fluid is a greenish blue color and my buddy's is clear on his Super Duty. We drained the fluid multiple times and its still greenish blue and mushy. Hope to find a solution about the soft brake pedal.

 

if you got air in the master cylinder, bench bleed that, then make sure to bleed the lines again. on a 1997 it'll have drums, make sure they are adjusted correctly as stated

 

It does have rear drum brakes and they are adjusted out so they barely drag the drum. I have bled over a gallon through the system and have clean fluid coming out of the bleeders.

I also bench bled the master cylinder until there were no more bubbles coming out.

I've tried pump & crack, gravity bleeding and vacuum bleeding and nothing works.

Is it possible for a vacuum leak in the booster to cause issues like this? Or maybe just air stuck in a junction/abs unit that doesn't want to come out?

I was also told by a guy at work that he jacked the rear of the truck up and opened both bleeders and the master cylinder and gravity bled them like that, making it easier for the air to escape and then doing the same with the front. He said it fixed his, but that was on a chevy 1500.

 

is the booster holding vacuum? if not you could try to change that next..seeing as you have done everything else

 

its not the booster... a vacuum leak creates a hard brake pedal, it will never make the pedal feel soft.

It could be air in the ABS unit... you will need someone with the electronic tools to cycle the ABS while bleeding if that is the case.

If you want the brakes to feel better, perhaps try replacing all the flex lines on the truck. I would do this before paying someone to cycle the ABS.

 

oh yea, i forgot :o