I lack enough professional experience to have an accurate sense of how often rebuild calipers fail early, but in the best case (and probably the majority of the time) a rebuild will be just as good as the original, and would last just as long. But of course you could get a lemon I suppose, or one that was built with inferior seals that would only last a few years. It would seem logical that rebuild quality might be contingent upon several factors that might or might not have anything to do with the brand. But in general, rebuilding calipers is not that difficult a process, especially for a pro, so I wouldn't have too many concerns in this situation.

What I do know, however, is that in general the lifetime warranties offered by Autozone, Kragen, etc., are more of a marketing tactic than an expression of superior quality. They know that the vast majority of their customers will no longer be owning the car in 3-5 years, and of those who are long-term owners of the cars only a minority will hang on to the receipts. So they know they will earn more business on account of offering the lifetime warranty than they will have to pay out because of it. So in short, the lifetime warranty sure is nice to have, but it doesn't necessarily mean the part you're getting is OEM quality. For a part that takes a lot of labor or a big hassle to replace (like the kickdown cable, timing belt, or strut inserts), I wouldn't bother with trying to get a lifetime warranty part unless I knew for sure it was also the best quality available. Replacing a brake caliper is not that labor-intensive, so I would tend to go with the lifetime warranty part, knowing that it was the last $$ I'd ever have to spend on that particular part on the car.

I agree with the others, check your rear brake hoses.

I have a similar problem with my 90. Three years ago after my driver's side rear caliper froze-up, I rebuilt my rear brakes with 2 rebuilt calipers, 2 rotors and new pads (FCP Groton parts). About 6 months ago when inspecting my rear brakes, I discovered that one piston in the driver's side rear caliper (same one!) was stuck. The system had a complete bleed at the time of the original brake job too.

Since the driver's rear rotor is warped, I bought one rebuilt caliper, one rotor and new pads from FCP Groton - strangely the passenger side is fine. Which makes me suspect that the driver's side hose might be bad...However, before I do the brakes this time, I am going to test the driver's side brake hose first!!

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90 244DL 252K - original engine/drivetrain :)

On my 1990 240 that I had since new I only had to replace one caliper and that was 10 years ago. Are you changing your fluid every 2-3 years? Another thing to check is the condition of the rubber hoses. If the have swell spots they can tend to act as pressure reserviors and keep the calipers from retracting properely.

I would do the rebuild myself so I knew it was done correctly.

I used to have a Toyota that had a terrible problem with rusting in its calipers. I got some grease that was compatible with brake seals and used it to help keep the moisture and dirt out. This extended the rebuild interval from about every two years to about 5 years. I sold the car when it was 19 yrs and 250k mi old. The original calipers had been rebuilt 3 or 4 times and were still working.

My bricks are both 15 years old and 225k miles. The calipers have never been touched, though I have some concerns about the hoses and master cylinders.

A properly rebuilt caliper should last as long as a new one. The problem is that most of the calipers you buy either mail order or over the counter aren't rebuilt all that well. If you want a near permanent solution, try www.whitepost.com . They overbore hydraulic cylinders, sleeve them in brass, and hone them to original size. I had them do a Triumph master cylinders about 14 years ago, and the guy who bought my Spitfire has never had another brake problem. I have no idea what they charge now, back then they'd bore and sleeve the cylinder for $40, then it was up to you to rebuild it. Now they do the complete job.

Other than that, I'd just buy the AutoZone rebuilds. They've never given me a hassle on any warranty replacement.

I've still got the original front calipers, never rebuilt, on the front of my
69 164 at about 290,000 miles. I used to have dragging problems because the
hoses were swollen shut. The little rubber boots are in bad shape and I
occasionally get some rust on the pistons (maybe every 4 or 5 years). I used
WD40 in the old days and Blaster more recently, pressed them out against worn
pads and pried them back in 5 or 6 times until they eased up and they are
still fine. I'll know I have gone too far when they begin to leak but they
have not so far....

Have you verified that your hoses are not swollen shut? Brakes work OK but
don't let all the way "go".
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George Downs Bartlesville, Heart of the USA!

I seem to be having the same issue, mine were used rear calipers. I suspect my brake junction box than the calipers.