Possible. I haven't pulled the wheels off, but inspecting through the wheels doesn't show any dampness. No external signs of leaking around the master cylinder. I had an Alfa that leaked back into the booster, I'm wondering if there is some palce for the system to hide a 1/2 pint of fluid. (I think the Alfa drank a quart or so before I figured out where it was going. What a mess when I cracked the booster open.