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Should I replace rear brake cylinders

A friend takes her car to the shop and they tell her she needs new rear drum brakes, new rear brake cylinders and a brake fluid flush.

There is no sign of any brake fluid in or around the brakes but they peal back the rubber boot around the cylinder and show her it is moist under the boot.

I offered to do the work for her and when I took off the drums the brake shoes did not look bad. As a matter of fact, the new shoes I bought had 4 mm of brake lining and the ones on the car had 3 mm of lining at the narrowest spot.

I think this shop was suggesting an unnecessary brake job. Clearly there is over 1/2 of the brake lining still there and no external sign of brake fluid leakage.

My question is … is a little dampness under the brake cylinder rubber boot acceptable?

If moisture is under the boot then fluid is getting past the rubber w/cyl seal. What is in question is what do you consider a little dampness?

If it were your car, I’d suggest that you keep an eye on the brake fluid level in the reservoir. As long as it isn’t changing and the brakes aren’t getting soft, there can’t be a whole lot of leakage going on.

Someone else’s car? I don’t know. Can your friend comprehend and follow instructions to check the brake fluid level?

Rear brake cylinders for drum brakes often aren’t overly expensive. Maybe replace it/them. Look up the specs for shoe material. If the brakes are solidly above minimum, return the new shoes. Check the wear on the drums. It’ll probably be OK. If it weren’t you’d likely have had the devil’s own time getting the drum off.

Brake fluid flush? A lot of folks believe that it is necessary every few years. But a lot of cars go their entire life with the factory brake fluid. If the brake fluid is discolored, I’d flush the system which is cheap enough, but time consuming.

The last time I had my car serviced, I was told that my rear drum brakes were also leaking at the cylinders. For the sake of scaring the customer, these shops make no distinction between “leaking” and “seeping.” Like I always do, I continue to keep a close eye on all of my car’s fluids. Eventually, I will either do the job myself or pay to have it done, but not at the shop that diagnosed the problem. Their estimate of the cost was too high.

Thanks for the comments. You re-enforced what I suspected. I am a believer in the saying if it works, don’t fix it. With my luck, I’d break off a bolt, loose a spring, and no doubt scrap a few knuckles and for what.

Maybe they had a new mechanic and needed a car for him to practice a brake job on.

Some good mechanic’s gloves from Walmart or the auto parts store can do wonders for those scraped knuckles.

Or better yet, find an independent hardware store.

I stepped on my safety glasses awhile back and needed a new pair.

Walmart = $13.98
Local Independent Hardware store = $2.98

Same brand, same model, same specs, exact same product.

“My question is … is a little dampness under the brake cylinder rubber boot acceptable?”

Yes, it’s quite normal…From your description, the brakes on this car seem completely serviceable…

I second Caddyman. Don’t worry about it.

I too think the shop has recommended unnecessary work.

If seals are seeping, a pile of black crud will accumulate at the seepage location. Absent a pile of crud or fluid loss, the brakes are fine.