Brake Rebuild

[TouchStone]

I'm rebuilding the donor car brakes and found that there is some pitting that has occurred on one of the cylinders. Is this enough pitting to affect performance? Should I replace it to prevent further damage? 3479934800

[Quiny]

I would replace those, as I recall I bought pistons and seals at RockAuto, they were not real expensive. They will probably work for a while but when the seal ends up at those spots as the pads wear you will get a soft pedal.

[Rasmus]

If you can catch a fingernail on it, replace. You'd probably never run the pistons out as far as the pitting but don't chance brakes. You need that system to work.

[AZPete]

That's a textbook example of when to replace the piston and seals. If you reinstalled this piston the pitted portion would nick the seal as it passed through it, so it will leak really soon.

[TouchStone]

Thanks for the feedback. I wasn't sure since the pitting looks so small, but as these are the brakes I thought it would be best to ask.

Also, their is rust forming on the insides of the other pistons, is this also a cause for replacement or can I just sand it out?
3486434865

[Quiny]

Inside piston rust doesn't matter as long as it isn't deep.

[suttonb3]

I just rebuilt my brakes and ended up replacing 4 of the pistons because of a similar condition. I think I paid less than $9 each on Rock Auto.