66-69 4 Piston brake caliper rebuild questions....

thrashingcows

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This for my 68 Coronet but since Ma' Mopar used the same basic 4 piston calipers on A/B/C-body cars, just different manufacturers I'm hoping someone may have some advice...

Finally got my reseal kits for my brake calipers on my Coronet. Got the calipers off the car and pulled apart and have been cleaning them and noticed that the pistons have some pitting and corrosion where the seals will sit and I feel that this will allow some seepage to happen past the seals.

Pics of pistons...Fresh out of the electrolysis rust removal bath....

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And the caliper bores are in great shape since I had them sleeved in stainless 25 years ago!

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So my question is to anyone who has resealed their calipers and had pistons in similar condition...did you do anything special to ensure a tight seal like add some RTV to the piston groove to help with the imperfections and pitting? Or did you just toss in new seals and assemble...did they weep or leak over time? Or are my pistons too far gone and I should talk to a machine shop about milling me up some new units?
 

detmatt

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I don’t see putting those pistons back into service. There looks to be pitting where the seal makes contact with the pistons.
 
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