I'm thinking it's the wheel cylinder. They're probably the original and it now has 239k miles. Around 31k miles ago, back in 2019, I replaced the wheel bearing and axle seals. It was quite an ordeal after a local garage failed three times to fix it. I bought the press fixtures, a press and fixed it myself. I watched it close afterwards and didn't see any axle leaks following my fix.

Today I decided to clean the layers of Fluid Film gunk out of my wheel wells to feel good after getting new tires and installing the Magnaflow Overland exhaust this week. I took the driver side drum off and was bummed to find fluid over everything. Judging by the pictures it I think (and hope!) its the wheel cylinder. It didn't smell as strong as gear oil, there was no oil dripping onto the wheel, no oil down the backing plate, and the bottom of the dust seal looks to be dry. The dust seal only had oily gunk build-up on top of it.

I monitor my fluids closely. Just about every fill up I look at the levels. My brake fluid is about halfway between full and low. I know I would have filled the brake fluid to the full mark the last time I worked on the brakes.

Would the brakes still feel pretty solid even with a wheel cylinder leaking? The pedal doesn't go the floor but maybe there's still enough pressure in the system even with a cylinder leaking?

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