Putting the petal to the metal can be fun, but not when it is the brake petal
During the past two weeks my 07 Expedition EB 4X4 20,800 miles has started to get a mushy break pedal and will slowly sink to the floor board with steady but light pressure.

The brakes still work, but I have a sinking feeling that not for long, so going to the dealer on the Ford extended warranty before I end up breaking something, like the car ahead of me for example.

Has any one had such a problem with their Expedition and know what was wrong? There is no fluid loss and the fluid has never run low so there should not be any air in the lines. Acts like when the master cylinder went out on my 73 T bird one time, many years ago. All this computer controlled ABS brake stuff is beyond me, so I don't have a clue.

 

usually thats a sign of the MC going out

 

Ok I got the 07 Expedition back from the dealer after three days of working on it. The vacuum booster was replaced and the master cylinder replaced, on warranty, no charge.
So how do the brakes work now? The same.

The brakes are still soft and the petal will still sink to the floor. I still have brakes, but not very good brakes. It is only a little better than it was before. The service rep said that all the new Ford brakes will sink to the floor and it is "normal". So I don't know what to do now and don't know if it is "normal" or not. It don't seem normal to me, but nothing seems normal to me anymore, so I don't know.

Anyway, here we go again, the dealer says it is fixed now, I say it is not.
It is always something.

Here is something I seen on line. Some Expedition and Ford truck brake problems can be fixed by going down a gravel road about 25 MPH and then jamb on the brakes. This activates the ABS and will clear any junk out of the ABS valve and gain a more firm pedal. Several people have tried it and it seemed to work.
So If you see a crazy guy in a Expedition on a dirt road acting odd, its me.

Also I am finding out the down side of an extended warranty. Something has to be "broken" to get it fixed. If something is a little "off" or not quite right, it does not qualify for "broken". So if the brakes are not quite right, they are not "broken". Broken gets fixed, not quite right is subject to debate and the dealer gets to determine if it qualifies or not. This leaves you to spar with the service department over what is broken and what is not.
It is a PITA.

 

My 2010 doesn't sink to the floor!

 

If the pedal is truly going to the floor, you should be able to show a tech and get it addressed. If it's just softer than normal, well it's Fords brakes. Try the dirt road theory. I have seen many many ford F150 posts on the soft pedal. Search around.

 

I am going to take it back to the dealer again. I don't know why problems like this can't be repaired on the first go around as they have the people there that only work on Fords and are factory trained. But I have found out that they seem to use stock answers like "they all do that" "its normal".

They insisted the vacuum booster was defective and had to be ordered so I had to leave the car there and get a rental car. I told them that I did not think it was the booster as the brakes seemed to have plenty of boost, but they bleed down under break constant pedal pressure. Then the next day they called and told me it was not the booster (surprise) and they had to order a master cylinder. So another day with the rental car. The next day I was told the problem is repaired and ready to pick up. I was told that the brake petal goes down a little more than normal, but the brakes work ok. I did seem better at first, but now I notice that the pedal is still soggy and I can still just push it to the floor board with not much pressure at all, like before. I still have brakes, but not like they were before the problem all started.

I have owned this 07 since it was brand new and the brakes worked ok up until a few weeks ago, so something has changed.

So I am going to try the slam on the brakes on the gravel road a few times to activate the ABS and maybe fix the problem. If not, back to the dealer again. The rental car again. The whole ordeal all over again. If you go in on a Thursday or Friday they will usually keep the car over the week end, so now I go in on a Monday morning.

BTW the rental I had was a 2011 F150 and I tried to push the brake to the floor and it was firm and would not go past about a inch and a half no matter how much pressure I applied to it.

The transmission has finally been repaired after only four years of Ford screwing around with it. I hope the brakes can be repaired in less time than the transmission took to finally fix.

 

I have been looking on line about Ford brake problems and have found that the ABS module can clog with dirt in the brake lines and cause a soft pedal and or the pedal to go to the floor. It seems that there are no screens on the lines and the valves in the unit are very small, so any little anything can cause a valve to malfunction. One guy kept replacing the master cylinder as that is what the book says to do if the brake pedal goes to the floor. The ABS unit was finally changed out and the problem was solved. It seems that a valve in the unit can get stuck and bleed the master cylinder pressure back to the master cylinder brake fluid holding container through the return line from the ABS unit.

So the fluid just goes around and around with any excess pressure going out to the brake cylinders to activate the brakes.
This is why the brakes will still work even with a soft pedal and being able to go to the floor with it.
There is no fault code because the computer thinks everything is ok as you only have a light application of the brakes, but you may be actually standing on them.

This condition is not covered in the Ford trouble shooting procedure "of course" so the fix is to replace the master cylinder, over and over (and over).

Kind of just a parts replacer mode instead of a troubleshooter mode. If it was the master cylinder last time, it is the master cylinder this time too.

 

Well I took out the 07 on a gravel road and did ten hard stops from about 30 MPH. The ABS did seem to work as far as I could tell. However the only result was that I had to take the Expedition to the car wash to get the dust off of it.

The brakes are about the same, no difference. But I thought I would give it a try anyway. You really have to get on the brakes to make a panic stop on dry pavement.

 

I found something else on line. It seems that on later model Ford brakes that if the calipers stick due to the grease on the slide pins getting hot and cooking off over time, that the brake pads will wear on one end more than the other. This can cause more problems than just a uneven wear to the pads and rotors.

It seems that when this happens, the brakes still work, but since the pads don't sit all the way flat against the rotors and the caliper / piston, they will clamp the rotors when fluid pressure is applied and will then spring back some pushing in the piston in the caliper back a little.

Now when the brakes are applied again, the fluid has to make up the extra clearance between the pad and the rotor first before the pad can clamp the rotor. The result is that the brake pedal can go to the floor trying to pump more fluid than designed to the calipers.

The braking power is less because of the uneven wear and the fluid pressure being lower because of the caliper piston filling up first before the braking action starts. A soft pedal and or going all the way to the floor can happen.

This makes sense as "normally" if the pads are all flat against the rotors / calipers and pistons with a very small clearance between the pads and the rotors, the total amount of fluid required to actuate the brakes is very small so the pedal travel is also very small.

One tech said it has become a common problem on later model Ford trucks. with some miles on the original pads. New pads, turned rotors, grease on the slide pins (usually) will fix the problem. Everything sitting flat and square as designed.

Might be worth a try as the pads are the original 07 factory pads with 21,000 miles on them.

 

"They all do that,its normal"

Translation

I dont what it is,i cant find it
now stop bothering me and get this
thing out of here.

 

Afraid so.

 

I'd put new pads and check/replace rotors. You'd be surprised at how much they'll be worn. Especially your rears.

After that, then maybe replacing the ABS diverter block

My thoughts also

 

Ask the service manager to post a $1,000,000 bond to offset the dealerships liability from sending you and your family down the road in a 3 ton vehicle with defective brakes.

Explain to him that $1,000,000 might not be nearly enough to settle all claims, especially any bodily harm claims, but you beleive the dealership's insurance coverage should help with that... provided it hasn't been revoked for sending other 3 ton vehicles down the road with defective brakes.

 

My post was deleted.

 

I am not sure why but my last post was deleted.
I finally got my brakes fixed, but I had to fix it myself.
There was air in the lines that I finally got out and now the brake petal is hard and will not sink to the floor.
Why Ford could not fix it, I don't know.

They work fine now, no thanks to the dealer, that had it for three days.

The Ford super duper extended warranty, so far, has been less than stellar.