[Gyoas759]

I periodically have to top off the brake fluid on my 77 coupe. (2.8 V6 with an auto trans.) I thought it was just a leak in one or both of my rear wheel cylinders and have been planning on getting around to replacing them. Recently the car has sporadically begun to gush huge clouds of white smoke. It's been happening more frequently lately. It's not often, usually while idling on a downhill slope, the engine will sputter a little and some white smoke will start clouding up around the car. When I get on the gas it unleashes a cumulonimbus cloud and then clears right up. The smoke doesn't smell like burning oil or coolant and my brake fluid loss seems proportionate the frequency of the smoking. (The more it smokes the less brake fluid I have.) Am I crazy? Is my mustang burning brake fluid? And if so, how and what needs replaced to fix it? Thanks for any help.

[1978CobraII]

I had the same troubles though it may not be the same thing. My Vacuum Modulator Valve for my transmission had gone haywire and was letting ATF into my intake manifold through the Vacuum lines. I would check your trans fluid and check your oil, because when I replaced my modulator I found 9 quarts of "oil" in my oil pan when it should have been 4-5. So I had not only been burning it but it was going past my rings into the sump. Needless to say my top end was very clean.

[Maurice]

It sounds like your master cylinder is leaking into your booster.Then it goes into the intake manifold.I had to replace both on my 78 cobra.