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Possible 2013 brake reservoir leak

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Was reading on another site about several people experiencing leaks in the 2013 models due to their reservoirs being overfilled. I checked mine and sure enough it was overfilled. Just wanted to pass the info along as brake fluid on your paint is not a good thing!
Mine overflowed and it was at the right level, on a 2012. I also had air in the lines. Also it looks like it leaked from where the res mates to the MC rail, as it was all covered in fluid but the res was clean on the outside and the fluid level went down by a couple mm. Once they fix my leaky caliper I will be keeping an eye on the MC to see if it does it again.
Mine was overfilled at delivery as well, seeping out of the cap and collecting on the flange separating the top and bottom halves of the MC. Interestingly, when I had the DOT 3 fluid swapped out for ATE Super Blue at a different dealer, they overfilled the reservoir. I know the hash marks are hard to see, but damn!
Just run it halfway between the seam in the middle and the top of the reservoir and you shouldn't have any issue even on track. It seems to vent more under track use.
The brake reservoir caps seem to have seeped since the 05 models, don't know if it is only if over serviced. Mine needs cleaned @ the seam every so often & the level is fine. Had the same annoyance with my 06 as well, I just wiped the reservoir seam every time I checked the oil.
Does it leak onto the floor? I'm leaking something onto the floor but it seems to be oil because my oil pressure sender configuration maybe isn't on tight enough. Haven' had time to check though...
Leaking from the cap is a pretty common problem with some cars at the track, there are insulating socks you can put over them (as opposed to the band that wraps around them) which a lot of people use just because it will catch the drips before they get to the paint. If it spits a lot, the band will not catch all of it. My guess is that it is due to the cap design, as I replaced the cap on my E30 BMW with an aftermarket one and it has not leaked a drop since while most people with stock caps have overflow issues.
I read a thread on this too on one of the other Mustang forums. Mine collects fluid along the half way separator line. The consensus on the other forums was that the plastic tank fill holes are molded incorrectly causing the caps not to seal well. The fix was cutting a circular piece of gasket material and putting it inside the cap for a tighter seal.

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