rear brakes

[strokerman11]

hey guys on my 03 f450 3 months ago the rear brakes went south and bad the rear calipers hung up and i had to replace the pads and rotors as i was putting it together noticed the calipers were leaking out of the pistons...so i replaced them also now 10000 miles later same thing happened but this time the slides on the calipers slid just fine but somehow the rear brakes need to be replaced again! so my question is what could cause just the rear brakes to be doing this? oh yeah the calipers were replaced again because they were leaking out of the pistons again

[Fordpowerstroke350]

are you sure brake fluid is not contamiated and eating the seals. i would completely flush the system for starters

[strokerman11]

did that twice now