I've noticed that there my brake fluid reservoir has a small leak around the seam where they attached the top and bottom halves of the plastic tank together. Not much fluid is coming out, but it's enough to wipe away and be able to see it come back slowly.

How hard is it to change the reservoir? Maybe a little clear silicon sealant around the seam might do the trick (assuming that brake fluid won't eat through it).

Has anyone else seen this happen? It seems pretty weird to me.

 

are you sure this isn't residue from fluid coming out of the top of the cap?

mine used to leak periodically (especially under hard braking) from the cap... I know it's most likely the DOT3 fluid. I stuck in some Motul RBF600 DOT4 fluid (just bled through the front brakes - safe to mix with DOT3) and it helped a lot. It isn't gone completely, but I'm hoping to get a chance to bleed the brakes entirely over my winter break.

Try seeing if anything is coming out of the cap. If not, you might want to have that checked out ASAP by your local dealership... hopefully you still have your warranty.

 

Mine does this as well but i think it comes out of the top and runs down the seam, an old sportbike tirck is to get a wristband like athletes wear on there wrist and put it around the cap...

 

Thanks guys, I'll take a closer look at it tonight and see if it is coming from the cap.

 

Over a year ago, when I first purchased the Stang and joined this forum, there were discussions about this issue. I copied the text of one user's post and saved it in my "files". My car has never had this issue so I never used this trick. Maybe it will help you.

REPEAT - the following are not my words - I copied from a year old post:
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The Brake fluid cap leaks on MOST of the S197 Stangs. some wors then others.

The fix.... wrap a wrap of teflon tape around the threads. (The same stuff you use on water pipes!).
I recall hearing someone mention they had seen a fix on The Mustang Source that some guy put a rubber washer under the inside of the cap and it solved the problme. The washer was purcahsed at Home Depot or soemthing like that. I have not been able to locate that thread over there but i have heard about it.
I went to my dealer and they replace the cap twice, but it still leaked. I fixed it myself by removing the cap, removing the rubber seal, placing the rubber seal on a plastic lid (like on a deli or margerine container) and then trimming a round piece the same size as the rubber seal.

Insert the plastice piece you just made insde the cap and then replace the rubber seal. Now put the cap back and that should be the end of the leak. My dealer said they would pain the frame rails where the brake fluis stripped the paint away. I need to make an appointment and bring it back.
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