Seized caliper

Phenolic and metal pistons have their own distinct quirks. The cylinder bore can always corrode, but you won't see the piston itself rust if it's phenolic, while a metal one can. Under very particular conditions (use on RVs in a well-known study, which sit unused months of the year absorbing water and not getting heated to drive it out), phenolic ones can swell, which metal ones won't. I think I can remember exactly one case on PriusChat of swelling being the cause of a stuck piston.

A metal piston will conduct a lot more of the heat of braking back into the brake fluid than a phenolic one will. A metal one might not chip or crack if blown from the caliper with compressed air without precautions, where a phenolic one might. (Blowing out either kind of piston without precautions is not recommended.) On balance of all these considerations, a lot of manufacturers have been moving toward the phenolics.

The "anti-rust coating" on the slightly-less-cheap rebuilt calipers is laughable; the one I bought for my Gen 1 was red powder in a matter of weeks. That meant my experience was exactly what the guy on the Porsche enthusiast forum predicted:

I assume, though, that the c caliper is aluminum, as they have been on Prii starting with Gen 2, which can make its own "anti-rust coating", so that might not be as big a deal.

-Chap

 

Maybe Toyota USA's silence on brake fluid change, coupled with the concept that Prius brakes are very lightly used, hardly need attention? Brake fluid accumulates water over time.

 

Anybody have a currently paid up techinfo subscription, or a copy of the c _New Car Features_ manual, to see the caliper specs?

-Chap

 

This was through Rock Auto, $36? That's the way to go.

 

Are you sure that Centric caliper is actually painted? I have had great luck with Centric rotors in the past, but not their pads or calipers. The 3K mile caliper warranty actually bit me in the butt on my last car after two of the units started leaking after less than a year. Having said that, I wouldn't have a great deal more faith in the Cardone calipers that are definitely painted.

 

Did it look nice, shiny, spiffy like this in the box?



So did the one I bought. Here it was five weeks after installing on the car:



Maybe yours will turn out to have a more effective "rustproof" coating. For $36? We can hope....

-Chap

 

Any time I change a caliper I also change the brake hose. I have been burnt in the past by not doing it.

I experienced one of those brake hoses that wouldn't let the fluid return to the reservoir.

 

New Car Features for the Prius c doesn’t have much to say about the front brakes:

1. OUTLINE
(a) A ventilated disc brake is used.

2. SPECIFICATION
Brake Type: Ventilated Disc
Caliper Type: PE54 (22V)
Pad Area: 38.6 cm² (5.98 in.²)
Wheel Cylinder Diameter: 54 mm (2.12 in.)
Rotor Size (Diameter × Thickness): 255 mm × 22 mm (10.04 in. × 0.87 in.)
Pad Material: PV565H-FG​

I couldn’t find anything that explains what “PE54 (22V)” means, though the numbers match the wheel cylinder diameter and the rotor thickness in millimeters, respectively.

 

That's fabulous! I always kind of thought the c was the spiritual descendant of the Gen 1, but now we know it's more than skin deep:



The part number is different from the Gen 1 PE54 though, so they must have changed something.

Hmm, the Gen 2 New Car Features used kind of the same designation also. It has a two-column comparison of the 2004 Gen 2 caliper to the 2003 Gen 1. It calls them both PE54C (but it says the pad material changed from PN540H-FG to PS558H-FF).

But we know the Gen 1 PE54C was cast iron with a steel piston, and the Gen 2 PE54C was aluminum with a phenolic piston (as is the Gen 3 liftback front caliper).

No end to the mysteries....

-Chap

 

So our sample size of 2 Americans doesn't fit the overweight 'Murican propaganda that you put out there.

If you have a high rate of elevation change on your commute, then yes, you could be using the brakes more significantly. Hopefully you're checking them more regularly as well since you fit into the severe conditions category.

I have a family and plenty of friends that I chauffeur around. Doesn't change the visuals of the car any... the Corolla still doesn't get 50+ and the full-sized Prius in 2012 looked like an egg. So blanket statements of "everyone else" is I'm sure isn't true.

I agree about the stealerships. Again, you are the first I've seen on Priuschat of any members complaining of a failed caliper, though. Outliers happen with any car or brand, that's why lemon laws are in place. Hopefully your newly purchased caliper will last longer and you don't experience the same issues Chapman was warning about.

 

I was just commenting that you threw out a blanket, "everyone else". If one doesn't do it, it can't be every one.

 

New calipers looking like ChapmanF's yet?