Brake caliper/pad "retaining" clips

[Roger Mills]

I've just replaced the front discs and pads on my wife's 20-year-old Ford Puma, and I have a query about the so called retaining clips. They are made of highly tempered steel wire and the free ends plug into holes in the caliper. They have loops which hook behind lugs on the caliper carrier. They look like this:

According to my Haynes Fiesta manual (Haynes don't do a Puma manual, but the running gear is the same as a 1995-onwards Fiesta) they look like this when fitted:

Anyone know what their function is? Is the middle bit supposed to contact the back of the pad? Mine don't - by 2 or 3 mm - see:

Sadly, I didn't make a careful enough note of what they originally looked like before I removed them. I wonder whether I have put them back correctly - but I can't see any other way they could go. The loops look as if they should go further onto the lugs - but if I tap the free ends further into the holes, they pivot on the caliper body and the loops move *outwards* rather than inwards.

Any informed comment will be greatly appreciated.

[T i m]

Aren't they just to provide a bit of resistance between the moving parts of the caliper to stop them moving too easily?

Assuming everything is sitting in the right place, then I think that looks right, assuming the clips are the same design / size as the ones you took out?

Your digital camera is your friend on this sort of thing (before you take it to bits). ;-)

Cheers, T i m

[Roger Mills]

Thanks. They're the original clips - I didn't get new ones. [The Ebay link was to show what the clips look like when not installed]

I'd still like to know what their function is. If, for example, it's to damp lateral oscillations of the caliper on its carrier, it doesn't need to be in contact with the pad. But if it's to push the pad away from the end of the caliper when the brakes are not applied - which would, in turn, retract the piston a bit and provide more clearance and less drag between pads and disc - it *would* need to contact the pad. I just don't know. It definitely doesn't retain anything. Nothing would fall off it it wasn't there.

Yes, I know - and I usually do. But I erroneously deemed it unnecessary on this occasion!

[T i m]

On Sat, 25 Jan 2020 22:49:05 +0000, Roger Mills [e-mail] wrote: <snip>

I believe that's their purpose. And to stop the floating caliper cover from flopping about, assuming the pins allowed such etc.

No, I don't believe it's for that Roger.

Quite. The only thing it might do is hold the caliper cover in place when you undid the two retaining pins (but only while you were working on it etc).

Doh! ;-)

As mentioned, as long as everything else is in place then the clip only needs to be pushed in till the main part was flush with the outer part of the cover.

The key thing is that nothing would fail even if they weren't fitted, they just keep the two caliper halves under a bit of tension / control to stop them slopping about (as I don't believe the clips would resist against much else).

A third opinion is a good thing though. ;-)

Cheers, T i m

[harry]

Their purpose is "anti-squeal" Stops high frequency vibration when the brakes are applied. There are various designs

[T i m]

<snip>

Most 'anti-squeal' solutions go between the pad and caliper / piston in some way.

I believe what Roger has there are more 'anti-rattle' clips that keep a bit of tension between the two caliper components, stopping them and the pads from clunking about as you go over bumps or steer etc (although there is some crossover on some designs).

Cheers, T i m

[Jethro_uk]

Aren't they meant to stop the shim that the caliper "floats" on from floating away ?

Other designs I've seen are simple bent wire pins that go into holes on the shims.

I think they're recommended to be replaced every time they are removed, but generally that's overkill.

[Dave Plowman (News)]

They're not retaining clips. They are correctly anti-rattle springs. Which may also reduce the chances of brake squeal.

[newshound]

Old ones may have deformed a bit over time. I never understood why this happened at ordinary temperatures until I asked a very good metallurgist from an automotive background. Even tempered carbon steel has microcracks within the structure and you can get plastic deformation at these sites that relieves local stresses.

Riders of old british motorbikes will know how valve springs shorten over time. Inlets as well as exhausts, although the exhausts shorten more. Car suspension springs also shorten a bit.

[Roger Mills]

You mean that they stop the caliper from rattling on its carrier? In that case, mine are probably fitted correctly. Do they look ok to you? [Link to photo in my original post]

[T i m]

Yup.

Because they help keep the parts together there is less chance of any rust / brake dust buildup holding the pads away from the rotor slightly and then squealing?

Cheers, T i m

[Roger Mills]

Don't think so. There are no shims on my setup. The single piston caliper can move sideways on its guide pins in order to centre the pads on the disc. But no shims to "float away".

[Dave Plowman (News)]

Just had a look - sorry, not familiar with that type of caliper.

[T i m]

No, not really, as the pins are usually a close sliding fit and there are often bellows to keep the dirt and dust out so they don't (typically) wear that much (if maintained properly).

Yes, assuming they are the right clips for that caliper (and the eBay link suggested they were) then they can't really be fitted any other way to do what they were designed to do..

Yes. If the caliper bits were allowed to just float about and assuming the piston(s) were very freely moving then you can get 'slack' in the sandwich, allowing the pads and moving caliper component(s) to clatter as you went over bumps and allow for more slack to take up when you pressed the pedal. By providing a bit of resistance (the spring in the clip), things stay together better and when the pads / rotor wear, the looped ends of the clips can move (slide) to compensate.

Cheers, T i m

[T i m]

On Sun, 26 Jan 2020 12:28:55 +0000, Roger Mills [e-mail] wrote: <snip>

To potentially put your mind at rest, the following link should be to a picture of a similar caliper with similar clips fitted to a Mazda:

And a Volvo:

And an Audi:

HTH. ;-)

Cheers, T i m

[Roger Mills]

Yes, they're the *original* clips. The Ebay link was just for illustration - I haven't bought any.

Incidentally, buying brake bits for that car is slightly fraught because Ford started fitting larger discs and pads part-way through 2000 - and mine predates the change. The first set of discs and pads I bought were too big, and I had to send them back. Presumably the calipers - and probably the clips - changed at the same time

Yes, that makes sense - thanks.

[Roger Mills]

Thanks for those links. The Mazda looks very much like mine - and the others are quite similar.

I reckon mine are ok - and I'll stop worrying about them!

[Fredxx]

Youtube is a good resource for reference.

Look at 50s into this, it's for a Ford Focus but looks the same as yours:

[T i m]

Well, unless you have had the car from new and only serviced it yourself (or never had it serviced) how can you be sure they are the original clips (and my point etc).

I know, you said. ;-)

Whilst I've always liked Fords (and built the kitcar from one) ... they had a reputation for (supposedly) using whatever bits were available at the time. ;-)

You are welcome.

Cheers, T i m

[T i m]

<snip>

NP. I thought they might offer some independent peace of mind. ;-)

Quite ... and they are pretty different in design, if not function from many of the other different ones I've dealt with across all sorts of cars, vans, motorhomes and motorbikes.

;-)

And as I said, the worst that would happen if they were the wrong ones, were tired or not fitted properly was that it would allow the brake assembly to rattle a bit over smaller lumps and holes (and maybe squeal in time etc). ;-)

Cheers, T i m