Imatk

Yeah you're going to want to take it in man... I know it sucks and I understand but he's right. Any spot you miss or if the surface isn't prepped properly it's just going to rust.

Unless of course you know someone with a bodyshop that could do it for you... but then you're back to taking it in... might as well have the dealer do it.

StangRalle

Thanks man! I'll get this at least sealed and maybe repainted if not too much of a hassle.

cmplxlgc

One of the first things i did when i took it home was use a irrigation syringe and get some of that stuff outta there below the line..no probs since....

justjim_pia

My '06 GT has been at the local (incompotent) dealer for 9 days now. The body shop and "service" department keep blaming eachother for delays. I feel like a general contractor having to work out the details between sub-contractors. Anyhow, they pulled the booster to get to all the areas in need of repair and managed to screw up the booster on the reinstall (causing another 3 days of delays). Anyhow, I don't drive mine in the snow yet, so hopefully anthing they have missed won't cause any big problems. I may try a bead of RTV on the top of the reservoir around the cap to make a little dam so I can wipe-up any that seeps out later.

Jim

07 HOSS Mustang

I wrapped the threads on the reservoir with 3 wraps of teflon tape and..NO MORE seepage. The leak was at the threads not the vent hole I guess.

whs

How many of you have taken your car in a second time for this fix? Mine was fixed in December of '06 with about 7000 miles on it. Fluid leaked down on the firewall and started to bubble the paint. The damage wasn't near as bad as the pics in the first post.

They replaced the master cylinder and fixed the paint. I've kept an eye on the master cylinder and wiped it off at regular intervals, to check for leaking brake fluid. Earlier this week it looks as if the leak has come back. I've got a little over 14,000 miles on the car now.

This does seem a bit ridiculous and wasteful. The car has been good other than this issue. I'm taking it in Monday to discuss the situation and hopefully get something done about it.

randy_tho

Is this still a problem on the latest 07's?

DoctorQ

I was the first post. Keeping my fingers crossed leak doesn't re-appear. Couldn't have asked for more from the dealership.. they kept car for 3 days and gave me a loaner during the repairs & repaint. I noticed they also dropped the brake fluid level a bit (it's still above the MIN line... used to be near the MAX line). I check the reservoir regularly, and still no leaks. Just curious, was yours leaking from the master cylinder.. or from the reservoir cap?

Scarpi

There was a post on this issue on 9/5/06 by "racerx" titled "my inexpensive fix for the brake fluid resevoir leak".
I did it in 9/06 and have had no leaks since then. Luckily, I discovered my slight leak before any paint damage. But this fix works and costs about $1. Check it out.

SD CALSPCL

After reading about this problem I went out and looked. Sure enough it was slightly discolored around the cap. I took the cap off and you could see the fluild in the threads. No damage to the firewall, as it hadn't had a chance to leak that much. Only had 1500 miles on her at the time. I cleaned it and wrapped the threads with teflon tape, as previously noted. No more problem. That was a great fix, found on this forum. Thank you to whoever originally came up with it. Honestly, I would never have thought of it.

st06vert

its not the firewall that has damage its under the steering shaft.

SD CALSPCL

I was cleaning the car this morning and thought I would check the brake reservoir just for the heck of it. No sign of a leak, so I removed the cap. Brake fluid was seepring into the cap threads and destroying the teflon tape. No telling how long before it would have been leaking again. So, if you have teflon tape fix, check it and make sure it is still intact. Mine was soaked through. I removed brake fluid down to just below the MAX arrow, and installed new tape. Time will tell.....

whs

It appeared to me that it was leaking from the cap, but on the work order they said the master cylinder was leaking. Of course there was no mention of the car having the paint fixed either. I'm wondering if this is a pressure issue with the system. Is this a problem exclusive to the manual transmission cars or do the automatic guys also have it?

I noticed one of the posters suggested that we just fix this ourselves and live with it. That is just doing the rest of us and Ford a disservice. People wonder why they have such a hard time acknowledging a problem and fixing it.

VegasGold

I have the leak also. I took it in for service and mentioned the leak. There solution....A new Cap...That was 4 weeks ago. Guess what? Still leaking. I also removed some fluid just below the max line. I will let my dealer know about the continued problem...

Yes, I am upset like most of you are. This has gone on for too long now. Is there really a solution for this problem???

whs

I would still like to know if this is a problem that both automatic and manual cars have, or if it just the cars with manual transmissions. It is difficult to tell since not everyone has that info in their profiles.

I did notice that since the weather is warmer there seems to be more fluid leaking from the cap. Over the winter and early spring it was barely noticeable.

Imatk

My friend has an automatic 07... it leaks.

I don't think it would make any difference what transmission you have.

Redfire05GT

First of all, let me say I have a 2005 GT auto and I too have experienced brake fluid leaks.
First the dealer replaced the cap, but it leaked again. I then tried the teflon tape thread wrap and it worked for a short period of time, but brake fluid disolves the teflon tape and the leak was still there. I just kept wiping it off.

Now for the kicker where I am concerned about the leaking of the fluid.
As you all probaby know, or may not know, brake fluid is hygroscopic by design and to a fault. The meaning of that is; it is designed to absorb moisture in the brake lines to prevent corrosion and other problems. (See StopTech.com technical papers on brakes for more info)

The disadvantage to being hygroscopic is that the brake fluid abosrbs moisture from the humidity in the air. Opening the cap will increase the amount of moisture aborbed. So what, you ask? If fluid is leaking out, air and therefore moisture is getting into the reservoir and fluid.

The more moisture absorded, the lower the boiling temp of the fluid. As we know, the S197 has a brake heat problem which can raise the brake fluid temp and in extreme high temps, and/or higher than 4-5% moisture content, can cause soft pedal and loss of braking ability.

So why this info paragraph? Call me crazy, call me silly, but I did a complete brake fluid change because my car is going on 3 years old and I live in Florida where it is humid much of the time and was getting softer brake pedal feel. I used Motul 5.1 DOT fluid because it has a higher wet and dry boiling temp than DOT 3 or 4 which is in the Mustang.

I have noticed I have no more brake fluid leaking with the higher boiling temp DOT 5.1 fluid and the reservoir is filled more than it was previously.

As Mustang S197 owners, we might consider the possibility that our brake fluid leaks are cause by the expansion of the fluid due to the high temps and possibly boiling of the brake fluid.

These are just observations and not definitive proof of the cause of the leaks, but, I for one, am happy I no longer have to leak problem.

m05fastbackGT

Took mine in today, and was informed, that it's the seams in the brake reservoir itself, and not the cap, which is causing fluid to leak..Anyhow, the dealership has already ordered a new brake reservoir, and will be covered under warranty.. In the meantime, I'll be sure to follow up, and keep everyone updated, in hopefully finding a solution..

Scarpi

Again! This fix works!! Try it! To find the thread do a search "brake fluid leak", then on page two find the one titled "my inexpensive fix for the brake fluid resevoir leak" by racerx. It has pics and all the details of how to do. Very simple and no more leaks.

whs

That is one possibly solution I've come to, the other being a poorly designed/manufactured resevoir or some combination of the the two. It does seem to get pretty hot under the hood on these cars, with the normal Summer time temps around here I've also noticed that the radiator cap seems to leak a bit too. I'm thinking having them change the brake fluid and investigation whether or not a heat extractor or cowl hood will lower the temps enough.

As for the guy suggesting the rubber O-ring trick, he might be missing the point that we paid for a warranty that Ford should honor. I shouldn't have to do their job for them. They've been building cars for what 90 some odd years now? You think by now they might accidentally get something right. It is on them to fix the car, this is a potentially dangerous scenario. I'm thinking someone should buy a new cap or use and old one and rig up pressure and temperature sensors on it and monitor the system during normal driving in order to determine whether or not it is boiling and blowing out past the seal on the cap.

It is doubtful that adding an O-ring could cause a catastrophic brake failure, but if you did and they did fail and someone decided to take you to the cleaners. Well that would be a bad deal.