Xantia Front Break Noise - Could it be the Bearing ?

KevMayer · Post by **KevMayer** » 24 Apr 2006, 21:49

After driving for a few miles my Activa starts to produce a squeeling sound from the front nearside (left) wheel.

I've had the wheel off several times. I've checked for sticking caliper. Everything seems free. I've even cleaned up the bottom pin and made sure that it lets the caliper slide easily.

I've adjusted the handbrake cable to make sure it doesn't bind. I've even re routed the handbrake cable out of its support loop on the strut and loosely fitted a cable tie to hold it in place (very loose..nice big open looP).

I've come to the conclusion that the problem is play in the wheel bearing. This is because the sound dissapears if I turn left but gets worse if I turn right.

Do you think wheel bearing play can cause this effect ?

The car has done 131000 miles. Maybe it's due new bearings ?

cheers,

Kev

Post by **Peter.N.** » 24 Apr 2006, 22:09

Try pulling the handbrake on gently while it is squealing, if it stops its something to do with the brakes, if not its something else. I have never had a failing bearing squeal, only whine or rumble.

KevMayer · Post by **KevMayer** » 24 Apr 2006, 22:15

Its not the bearing that squeels. Its a brake pad squeeling noise, but my theory is that the play in the wheel bearing allows the brake disc to tilt and hence rub on the brake pads. Turning left stops the noise. Turning right makes it worse. This could be a result of the disc leaning different ways as I turn in different directions...maybe... what do you think ?

The caliper and pads are fixed to the hub whilst the alignment of the disc in the caliper relies on a good wheel bearing ? Worn bearing equals disc movement..... does this sound sensible..... ?

I pull the handbrake to stop the squeeling whilst driving through town. It stops the embarassing noise a treat. Must do wonders for my fuel consumption (not!).

So, I've tried everything I've picked up from this forum and still it squeels like crazy.

Could it be a sticking caliper piston or faulty handbrake adjuster ?

Is a new caliper the solution ?

Kowalski · Post by **Kowalski** » 24 Apr 2006, 22:46

You could try adjusting the auto adjusting piston on the caliper a quarter turn (or less) back to give a little more clearance, that might make the noise disappear.

KevMayer · Post by **KevMayer** » 24 Apr 2006, 23:14

Thanks for the suggestion. But, I already tried that.

I took the pads out and wound the piston back in and made sure one of the notches lined up with the pip on the back of the pad.

I copper slipped the pads.

I lubed the rubber sheath on the top sliding pin.

The caliper slides in and out nice and freely.

It still squeels !

Mandrake · Post by **Mandrake** » 24 Apr 2006, 23:35

Internally collapsing brake hose preventing the pads from fully releasing ? Known to be quite a common problem on some cars, although I don't know about Xantia's.

The suction caused by releasing the brakes causes the inside of the hose to collapse, blocking the flow, but applying the brakes expands the inside allowing the pressure to go on. Effectively the hose becomes a one way valve.

It's caused by the inner most layer inside the hose delaminating from the rest of the hose, creating a thin weak section that cant withstand the suction. There is no visible sign of this on the outside of the hose, so the only way to rule it out is to replace the hose.

Pad surfaces ? Have you done anything to the pads when you've taken them out ? What do they look like ? Does it start squealing as soon as you put them back in, or does it take a few days ?

Are they really binding and thus getting hot, or is the noise the only symptom ?

Have you tried putting a slight chamfer (about 1mm at 45 degrees) around the edges of the pad surface with a rasp or file ? I do this as a matter of course with new pads, and if there is any lip on the edge of the disc and you don't do this you can sometimes get squealing..

Poor grade of pad ? (Too hard, or wrong materials) Using a "brand name" of pad isn't a guarentee that its a good or suitable pad for the car... often pads are too hard in the name of long life, but they then squeal a lot and don't work as effectively either.

If the wheel bearing was worn enough to allow enough tilt to make the brakes squeal then you should be able to detect that by jacking up the corner until the wheel is off the ground and grasping the extremities of the wheel and trying to wobble it. If you can't get any wobble I seriously doubt the wheel bearing is the culprit...

When wheel bearings go, they seldom ever give any detectable slack, I've had wheel bearings go on a variety of cars over the years and in every case the symptom is a low droning or whiring noise at speed on smooth seal, and yet no slack is detectable in the bearing and it passes the MOT, even when the noise gets quite bad. If you don't hear an obvious droning noise at speed on smooth seal once again it is highly unlikely to be a faulty wheel bearing.

Regards,
Simon

Post by **Peter.N.** » 25 Apr 2006, 08:14

If the bearing is worn enough to allow that sort of movement, I would think you would be able to feel the movement with the wheel jacked up. Squealing only usually comes about when the pad is in very light contact with the disc, they used to put 'anti squeal' shims in the early disc brakes, which tilted the pad slightly. It used to be a good sign with drum brakes if they squealed, usually meant they worked well!

The only really practical suggestion I can make, is that you try some different pads.