The first Centric caliper I installed became entirely surface rusted in two weeks. During that time, the car was driven four miles, parked on gravel, and experienced two brief rain storms. It was not exposed to any road salt.
The second Centric caliper I installed had started to surface rust after only eight days, two miles of driving, and one rain storm.
Compare these to the NAPA Total Eclipse calipers (actually Cardone) previously on the car. In the below picture, the right was installed under 2 years and 3000 miles ago. Its black coating is firmly attached, showing only a few spots of rust breaking through. Its piston easily extends and can be pressed in by hand. It is back on the car working great. The left was installed 3.5 years and 32k miles ago. Its piston head is severely rusted and a cut boot caused it to rust in place in the bore. Like the Volvo rebuilds, it appears that it is surface rusting beneath its black coating, causing the coating to flake off. Still, its caliper bracket was nicely coated (except for rust spots right where the pad ears wore away the black coating; the most important part). Maybe that would have been better than the Centric bracket which immediately rusted.
To their credit, the Centric rear calipers used the boots with internal metal bands to hold them in place. The Volvo rebuilds used the apparently cheaper boots with external thin metal clips. I suspect those will rust and fail, possibly allowing the boots to fall off. I will replace the rear caliper boots on my Volvo rebuilds with official ATE boots which use the internal metal bands.
Paying more for Volvo calipers seems like a waste. Two of the six I received were rebuilt from disfigured cores. That base metal is a total crapshoot between Volvo and aftermarket. The machining of pad-holding surfaces seemed equally good between Volvo and aftermarket. Aftermarket front calipers represent a much better value because they include rebuilt brackets. Save money by purchasing aftermarket rebuilds, spend those savings improving the rebuild quality yourself.
In rust-prone areas, calipers will fail due to surface rust in three to five years. I feel the only solution to stop this cycle of failure is to send newly rebuilt calipers for professional stripping and powder coating. Expect about $450 for this job, including Cerakote on the piston heads. Add in new ATE piston boots and stainless Volvo pins and springs for even more longevity.
Or just send your nasty rusted calipers back to FCP for replacements every three years before they fail and destroy your pads and rotors on one side, requiring new pads and rotors on the other side as well. Maybe FCP will get sick of paying on warranty claims and use their influence to force rebuilders to do a better job.
The fault lies with the terrible rebuild quality and general lack of rust protection on all Volvo replaceable components. Not all cars are like this. My 2002 Mercedes suspension components look amazing compared to my Volvo which lived in identical conditions for almost the same amount of time. Quality is possible.
(Edit 5/31/23: I had labeled the rusty calipers as Cardone when really they are Centric. One failed after 15 months.)
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