Best rebuilt brake calipers?

I have one rebuilt caliper and still have it... 11 years. The thing about rebuilt caliper is you have to buy the one you replace unless you replace both side... meaning if you have a Bendix there, you must replace it with Bendix.

Otherwise you need to buy a pair to match the calipers... like switching to ATE...

I buy my parts online but have not bought rebuilt caliper since then.

Tiger, Do you do any maintenance to your rebuilt calipers? Like re&re them once a year? Mine op for about 3-4 years then they're shot. AJ

Maybe putting high quality pads on them is the ticket? It sort of sounds like yours got extended very fast? Although there is no way those boots should just pop out like that.

I did nothing to them... no maintenance whatsoever.

I disassembled the caliper to take a better look at it. This is an 80

300SD with Bendix rear calipers. The rubber piston boots are held on by a thin split ring that goes over the boot and holds it to the caliper. Somehow, all 4 of these are off both calipers. And they must have come off fairly early, as the boot was still folded back. If you open it up, the rubber in the folds looks brand new.

I tried putting the boot and split ring back on just to see how well it holds. This doesn't appear to be the greatest design. The ring sits on top of the rubber boot and relies only on the tension to hold it to the lip of the cylinder. If you imagine slipping a rubber boot on the end of an 1 1/2 pipe and fastening it with a thin split spring ring that sits at the very edge of the pipe, that's the idea. It does seem tight, but not a great design. If the ring somehow moves 1/8 inch, it will just slip off.

I see as replacements there are also ATE and Girling calipers available. Does anyone know if these handle securing the boot differently? I'm left wondering if the split ring wasn't installed all the way on or if there is some other mechanism at work, like expansion/contraction with heat that works it loose? The originals were Bendix too and they lasted 20 years, so I'm leaning toward the rings not have been done properly by the rebuilder.

One thing for sure, this time I'm going to take a close look at the boots before I put them on. The last ones came loaded, so it wouldn't have been obvious if the rings were not on right.

They all hooks on the same way regardless of brand... I have seen them. Like you said, it is all tension strength... the ring should have been hard to remove... you have to coax it out with big screwdriver.

You can try a bit of red loctite to make it stronger. The boots simply slips on with notch and tension strength.

Verify that your discs are to spec as well... If they are too thin, then perhaps the calipers are hyper extending?

Logical, but the discs were brand new and are still fine. I unfolded the boots and most of the boot area, ie in the folds, was clean and brand new. They never extended much at all and it looks like they must have come off early on. I'm going to check the new ones prior to putting them on.

Another interesting thing I learned. According to the shop manual, the pistons have a high side and a low side. Depending on the type of rear suspension of the particular model, the high side is supposed to be rotated so that its at the top or bottom of the caliper. The only thing the manual mentions this is for is to reduce squeaking. I never checked the rebuilt ones I put on last time, as they were loaded. Taking them off, I see the pistons were rotated so the high side was vertical, which wasn't right for any model. Probably had nothing to do with the boots, but they did squeak when I backed up. This time I'm gonna watch that too.