Braking Problems/Defects in a Ford Edge

Maybe a small leak, sometimes leaking out brake fluid and other times leaking in air. Because air is compressible, it would make your brake system "spongy." Bleeding air and recharging fluid is a "band-aid" repair; it is best to track down the leak, if that is what the problem really is.

More then likely a seal is allowing air to inter into the system. Main cause I have found over the last 10 years has been from the master cylinder area. As the peddle is returned to the fixed position air is drawn in. Because there are tow separated sides to a brake system now days it should be easy to pin point which side air is getting into. If they only have to bleed the back brake to improve the issue, then master is problem. If they only have to bleed the front, then calipers are drawing air in passed one of the seals on the retract stroke. Any good tech worth their salt should be able to fix this. If you still are not getting the issue resolved call engineering department at Ford Motor company. I have done this in the past and found lots of get ways to around issues on their equipment.

Good Luck

Another possibility that has appeared quite often is the master cylinder is leaking and is pulled into the engine through the vacuum line and is then burnt and discharged through the exhaust. A indicator of this would be the loss of brake fluid that could be in a very small amount because once the air was drawn back into the brake master through the same defective seal you would then be unable to create enough pressure for the brakes to work effectively because the air would compress and not build pressure. You also want to make sure that they are using the correct fluid because the ford brake fluid has a boiling point of 550 degrees for dot3 which in most aftermarket fluids you have to go to dot 4 to achieve these temp levels. If they are using a different fluid then you could have a situation of the brake fluid boiling and therefore there would be a situation created that would actually leave a gaseous state inside the system. Good Luck

Agree.....Air can enter the master cylinder at the last washer [secondary] and it does so if the filler-cap of the master cylinder has a blocked air vent. This air will bleed out to the master cylinder reservoir on its own and need not to be bled at the wheel cylinders.

Air can never enter the system at the caliper seals or wheel cylinders.

Thus make sure the fillercap is vented.....if ok then replace master cylinder kit.

I once had a similar problem with a VW Scirroco some years ago. Turned out to be a build up of brake dust in the rear brake drums. The cure was to drill a series of holes in the side of the drum as close as possible to the braking surface to let the dust out. This also had the side benefit of letting any water out.

Regards,

Tony Lee.

Although I feel the main problem has been properly diagnosed by several people here already, I would just like to mention an extra fix that will help once the air leak problem has been fully solved, or simply improve almost any car's barking system.

It is to replace all the standard flexible lines between car and brake with heavy duty ones having a woven (stainless?) steel mesh covering the plasic pipes....they improve pedal feel by about 2000%.

Go easy the first time you drive after replacing them as the brakes will react far quicker than they did before!! Once you are used to the change in "feel" you will never go back to the manufacturer's standard issue.

"Barking system"? And his pic is a dog. Put me in the camp that says just replace the MC and bleed the system, problem solved.

Don't knock it till you have tried it......

To properly bleed these brakes they have to use a scanner and pulse the valves in the anti lock brake system. Try a different dealer and really complain.

Check to see what material the disc brake caliper "pistons" are made from. Most vehicles use either a steel chrome plated piston. Or a thermo plastic phenolic piston. Of course the plastic is for weight reduction and cheaper to purchase. And as in most cases. Cheaper is not necessarily better. Replace the plastic with steel. Problem solved. It has to do with the repeatability of the piston retract distance. The steel out performs the plastic by a fair margin. As well. I am sure any honest auto mechanic will tell you. On a plastic piston. The face the contacts the brake pad. Although sometimes covered with a thin metal cover. Crumbles into dust and small chunks of plastic as a result of the extreme temperature variations resulting from braking.

You think his system would degrade that fast? The car is only 2 years old (if that)

Ford originally released the vehicle with plastic pistons. And within the 2nd year changed the design to incorporate steel pistons for the very reasons being described. I have brother that purchased the Edge. Before he even purchased it I warned him of the potential problem. He complained of the spongy feel soon after he purchased it. And within a year or two had brake failure and had to be towed. In some cases. If the piston doesn't retract enough. It can drag. Defeating the fuel economy purpose of the light weight plastic piston. And creating extreme heat build up. As it was in his case.

Ford eng.. Along with most other NA vehicle engineers know of this. I know they do. Personally.

Thanks to all you guys for all the information. Will follow up on those tips.