The plumbers tape method works, just don't get any in the brake fluid reservoir.
Wrap a couple three wraps around the threads (what thread there is) and then replace the cap. Keep an eye on it, but that seems to fix it.
You would think Ford would know and fix this by now.

 

Moved this topic since it is not "GT performance related" since it affects the V6 models as well. Glad you guys posted this info. I just took a look at my car and found the same thing.

 

I also had a trace of brake fluid on the top and seam around my resevoir. No paint damage though below. But since I hand tightened the cap and wiped off the resevoir it seems to be dry after some driving. I must admit I really "hand tightened" it very tight. Does anybody know if teflon tape will work on the threads like plumbers tape? Is it the same thing? I have some teflon tape used for pvc pipe. Come on there must be some plumbers out there. Thanks.

 

Ever see what brake fluid does to Teflon tape? Just like paint, it dissolves.

 

Thanks for the info. I won't use teflon tape.

 

So what I'm reading is there is not fix for this?

 

I am trying something new.
I have a rubber gasket that I found on a fairly new oil filler cap. It is the exact same OD as the ID of the cap.
I removed the cap and took out the rubber and placed my rubber gasket in between the cap and the rubber. I had to trim the inside of my gasket because there are 3 nubs in the cap I wanted to clear.
I carefully put a little extra down pressure re-installing the cap so I wouldn't damage the plastic engagements ( i.e., threads).
I report back after a few more miles and tell you if it really works.

 

mine seeps too- 'looks' like the seam, as thats where it collects, but it comes from the cap and dribbles down- gotta wipe it off every couple weeks before enough collects around the seam to drip off. Ive heard if you remove enough brake fluid to bring it down to about the midpoint between add and full, it stops...read somewhere the gasket just has a couple slits for breather...not good as its gonna get moisture inside too. Ford really needs to make a 'bellows' type gasket that can suck down in like on the oldschool iron masters...would be difficult though as the reservoir is so large. bad thing is Ive forgot, havent wiped mine off for a few weeks...- think I'll go check right now before I forget again.

 

careful there- I think the original has cuts for breather- if a solid gasket placed above it, could lead to vacuum in the reservoir as pads wear, causing pedal issues, or cavitation in the abs pump if it tries to activate.

 

The original rubber has room to move. In the old days, you would see the flexible part of the rubber pull in as it needed to. I'll see what happens. I may actually need to "check my fluid" like in the old days.

 

I just went out and checked mine again- pulled the cap this time- youre right, its got a bellows instead of a breather(I'd read it had a breather, but never took it off to look). man that cap is a POS...felt like it was the wrong size or something, not much engagement...mine still hasnt dripped off yet, but like I mentioned, usually wipe it down every couple weeks. saw a thread somewhere wher a guy put a elastic bandanna thing around it- to dress it up and hold the drips before it got on the paint.

 

SO FAR, DRY AS THE DESERT!!
I put the car on inclines and drove through sharp curves and so far ...nothing!!!
I'll post if anything changes.

 

I have had Ford replace my brake fluid resevoir cap once, but the leak is still there. I tried the teflon tape, but it started to leak again shortly after that trick. What should worry all of us is that the fluid leaking out means humid air is getting into the reservoir to replace the leaking fluid. Why is this a concern? Because brake fluid is hygroscopic. That means it easily absords humidity from the air, which in turn reduces the boiling temperature of the fluid. The fluid leaks occur when the brakes are used and heat builds in the fluid. The leaking and absorbtion of water vapor from the air reduces the boiling temp and decreases brake fluid efficiency. Has anyone else noticed your brake pedal is softer and travels further now after several thousands of miles compared to when it was new? This is a safety issue. Ford needs to fix this soon or they will face some brake failures and law suits.

 

Yeah I have the leaking but seems to be around the center seam of the reservoir and not the cap.

Although I suppose it could leak from the cap and down into the seams, but it's dry as a bone around the cap.

 

I wonder if they (FORD) will pull the motor and paint my engine compartment under warentee or blame the leak on my aftermarket Shaker, CAI, Tune, Spoiler, ect, ect, ECT!!!!!!

 

I have the same issue with my car, I wipe it off all the time. It seemed much worse when it was hotter as well as doing a lot shifting,

I tried a piece of extra rubber with a slit cut in it, and it worked for about a month last year and it seemed the plastic cap stretched out of shape.

My buddy has a 2001 Escape, and this exact issue occurred, the dealer replaced the master cylinder 3 times, before Ford released a revised cap, it has not leaked since.

Every Mustang I've seen does this. Thankfully I have no stripped paint because I've been wiping off the top every so often.

FYI - My dealer has replaced the cap twice so far.

 

My dealer left the cap and removed some of the fluid and it still does the leaky-seepy thing. Next O/C will include this little issue and that TSB for the hesitation!

PS: Thanks for the reminder to check paint!

 

???? They finally came out with a TSB for that?? Mine did it today for the first time in a LONG time!!!! Still not bad enough to take all my mods off and go in for service though. Has anyone done it yet?

 

I just check my 06 GT and its leaking too. It looks terrible a nice clean engine bay but then grim trapped on the brake fluid reservoir! Im going to take this into my dealer along with my complaint of vibrations while braking and a pull to the left while braking.

 

No leaks ever since I really tightened the cap by hand a couple of weeks ago and cleaned off the top of the resovoir. I just checked it and the top of the resevoir is totally dry.