I topped up the fluid level in the rear brake reservoir about a month ago. Today, it's down about 3/4" (about halfway between the low and high marks). I removed the rear wheels- no obvious signs of leakage. I traced the brake line forward to the tranny and from the engine back- no leakage apparent. It's too greasy around the tranny to tell anyway. The rear brakes were completely redone about 2 years ago, new wheel cylinders, shoes, etc. the pedal feels the same as usual. It has been some months since I had the Z out on the read. Any ideas?

Thanks.

Put clean paper or cardboard underneath all your braking components, start your engine, stand on the brakes, read a paper while you're doing that, and then 30 min later, see if you have a drip anywhere? You can of course remove your drums, put pieces of paper underneath the wheel cylinders, and reinstall the drums for this test.

On a '72, I believe the rear reservoir feeds the front brakes. Check for leaks there as well.

If there are no obvious leaks in the lines or the wheels, it may be leaking from the back seal into the Master-vac.

Rear reservoir

FRONT RESERVOIR

Do you know what reservoir is for the rear?

Do you know what reservoir is for the rear?

The small one.