outside brake pad more worn?

On every single-piston caliper I remember, if the piston (on the inside) doesn't move, neither does anything else and that caliper provides no braking effort.

You might want to re-think that one again. If the brake is a floating caliper design with the piston on the inside, no pressure on the inner face of the rotor means there's no braking at all.

"That Tune" wrote in news:in5sml$i0$1 @speranza.aioe.org:

That's a different kind of problem from what the OP reported. And, generally speaking, calipers do not fail in this manner.

Pedal-pressure creates immense forces that will overcome any resistance to outward piston movement, but RETURN forces are tiny by comparison. Rusty pistons typically allow normal braking effort, but will not let go afterwards.

dsi1 wrote in news:in5v45$6no$ snipped-for-privacy@dont-email.me:

That would only happen if BOTH the inner pad were totally stuck AND the caliper sliders were totally stuck; a rather unlikely occurrence.

in theory, that's true. but dude, some of the remans are complete garbage.

i've just taken apart a pair of cordone's that were starting to stick. the previous owner had them installed about a year ago. and those things are hideous. they were acid etched to clean, but left in the solution so long, the tolerances are shot to heck. and the main upper slider pin [honda] is not only loose it's so eroded by the acid, it's rougher than guts so any sliding is notchy. and the end seal's one-way air/grease valve has been capped!

terrible terrible rebuild.

so returning to your point, yes, /good/ rebuilds are worth using as replacements, and yes, the o.p. needs to be safe and thorough on any work, but i think cheap remans are a liability. i'd never use them on any vehicle i owned - i'll always service and recondition the originals.

and when that "not let go" happens with the sliders, it causes precisely the situation the o.p. described.

I see your point now. You're talking about the pad being completely frozen to the adapter, not the piston. I've never seen that but then again, I've never seen a lot to things. Thanks for the clarification.

Yeah, sure, trust your calipers to some 9 year old Mexican kid

or you can have your brand new g.m. calipers made by some 9-year old chinese kid with congenital myopia.

one more caution to add to the low quality rebuild thing - when rebuilders "clean" calipers in their acid bath, all the original corrosion-resistant cadmium plating is removed and not replaced. for the most part, this is more a cosmetic thing than anything else, but there is one critical area where this becomes vary important - the root of the "claw" that grips around the disk. if that root gets to corrode because its protective plating has been removed, the rust pitting can initiate fatigue, and the claw can break. i really wish i still had a picture of it, but i did some work on a vehicle failure where one of the toes on the claw had fatigued and cracked off. fortunately for the driver in this case, the other toe was still there but nevertheless, this was a potentially life-threatening safety flaw and one whose onset could have been prevented by avoiding misguided/low quality rebuild practices.

Steve Austin wrote in news:4d972097$0$14344$ snipped-for-privacy@news.westelcom.com:

Wanna see aftermnarket rebuilding? Here's a YouTube video of driveshaft remanufacturing:

Watch the WHOLE thing, and especially watch what this guy does with the hammer and griding wheel to these precision-made components!

No need for a flame.. I basically agree with what you say above.

You have choices other than buying a rebuilt caliper:

(1) you can buy new very cheaply in many cases now, with the new kit including pads, etc.

(2) you can rebuild the caliper yourself. It isnt hard to do, in most cases, and not so expensive in terms of parts. You dont really need any expensive special equipment either. Just dont twist the bleeder off in the caliper body as I once did.

Doesnt inspire a lot of confidence, does it? Wonder how many of these fail early... You have to know your supplier, basically. Some people make junk, others make good products. It is that way with just about every rebuilt item I know about.

while it's possible the "grind" in the video is all they do - and based on the filthy conditions and unsafe work practices, it wouldn't surprise me in that case, but it's also possible they're just doing a rough "wear removal" grind that removes pitting ahead of a precision grind like this:

but flame hardened componentry isn't as good as carburized [like old-fashioned honda joints]. if the boots remain intact and the guts kept grit-free, carburized will last hundreds of thousands of miles. flame hardened maybe a third of that, even with good boots.

We have chucked the piston up in a lathe and polished it with crocus cloth, moistened with a little oil or kerosene. It doesnt take off any serious amount of metal but will polish the piston like a jewel.

Same with the cylinder bore in the caliper... Polish it, dont machine it.

Then clean them very well and dry them.. Reassemble with the new seals using a little bit of brake fluid for lubrication.. They can last a LONG time if they are not really corroded seriously.

Paul in Houston TX wrote in news:in38s0$65j$ snipped-for-privacy@dont-email.me:

not really, all inner pads ride in a grove of some kind. KB

I'm quite well aware of both what the OP reported and how a caliper functions, but was responding to your risible analysis here: news:Xns9EBADFA1DCD2Ategger@208.90.168.18

Not true.

but RETURN forces are tiny by comparison. Rusty

Yes, but that would result in wear to both pads. If the sliders are free, rotor runout and vibration or wear to either pad (or if the inner can retract at all) will result in a separation of the outer pad from the rotor enough to prevent further wear to that pad.

"hls" wrote in news: snipped-for-privacy@giganews.com:

Which is my preference when working with OEM calipers.

And even with those rear calipers that incorporate a parking brake. So long as the parking brake mechanism is sound, the piston and hydraulic seal can easily be replaced.

Here's what I did to mine last summer:

Fronts are easier because you take the whole thing apart.

I think that may be dependent on the automaker. A piston alone for a Honda is about $80.

An air compressor is nice to have.

that's not a great idea if it's a plated piston though - it will remove the plating.

brake fluid is not good for reassembly because it can cause corrosion in the presence of [unavoidable] water. you should use a proper brake-specific grease compatible with the brake rubbers.

like this:

again, avoid relying just on brake fluid for assembly lube - it will cause corrosion problems.

ensure you thoroughly clean any spilled fluid off any metal parts after refitting any brake components.