Brake noise possible found cause

[RHYSF00]

So i had been having a high picth noise when applying light to medium pressure on brakes since march. Have spent a while looking for cause. After some research i found that the cause could be with the slider units in the caliper. However could it be the actual caliper it self? Heavy breaking no noise. Car still slows down. 

[Red_Corolla]

It won't be the caliper or the slider pins, noise like this is caused by vibration at the points where the pads contact with the caliper and carrier bracket. The cause is normally build up of corrosion and/or the anti-rattle components have worn out. Said components are normally shims fitted in the carrier and a coating on the backs of the pads, or sometimes the pads themselves are shimmed on the back.

[oldcodger]

9 hours ago, RHYSF00 said:

Have spent a while looking for cause.

Do you mean looking on the web or at the actual car brakes ?

Are you doing it yourself or a garage ?

A basic strip down  and clean of the brakes may help find the source.

As said cleaning  and relubricating the shims and pads etc,  with something like Mintex Ceratec rather than copper grease, as they are essential regular maintenance items, as are the slider pins which need red or silicone grease.

Also examine the state of the pads, is one pad worn down more than the other etc.  Check the discs thickness and for surface uneveness etc.

All basic stuff well covered in the Haynes manual.

You say the problem started back in March, had something been done to the brakes  just before ?

[RHYSF00]

11 hours ago, oldcodger said:

Do you mean looking on the web or at the actual car brakes ?

Are you doing it yourself or a garage ?

A basic strip down  and clean of the brakes may help find the source.

As said cleaning  and relubricating the shims and pads etc,  with something like Mintex Ceratec rather than copper grease, as they are essential regular maintenance items, as are the slider pins which need red or silicone grease.

Also examine the state of the pads, is one pad worn down more than the other etc.  Check the discs thickness and for surface uneveness etc.

All basic stuff well covered in the Haynes manual.

You say the problem started back in March, had something been done to the brakes  just before ?

I have renewed the brakes in march as it was needed. I cleaned everything before replacing parts and greased wherevi ment to grease. There was no sound for a few weeks then it started. 

[oldcodger]

Might be worth taking out the pads and seeing if the wear is flat and even .

What brand pad did you use, sometimes changing brand can make a difference.

Did your new pads have a wear /squealer metal tab ?  could that be catching ?

Did you get the brake slider pins back in the right order, eg the rubber tipped one in the trailing edge of the caliper.

Also check around the drive shaft, rubberboots/clips and abs relector ring etc for any loose/broken bits etc,

 

[RHYSF00]

12 minutes ago, oldcodger said:

Might be worth taking out the pads and seeing if the wear is flat and even .

What brand pad did you use, sometimes changing brand can make a difference.

Did your new pads have a wear /squealer metal tab ?  could that be catching ?

Did you get the brake slider pins back in the right order, eg the rubber tipped one in the trailing edge of the caliper.

Also check around the drive shaft, rubberboots/clips and abs relector ring etc for any loose/broken bits etc,

 

Brake fit for pads. Only removed one bolt to replace calipers. Have got a wear indicator on. Driveshaft no faults

[TonyHSD]

2 hours ago, RHYSF00 said:

Brake fit for pads. Only removed one bolt to replace calipers. Have got a wear indicator on. Driveshaft no faults

This could be the problem. One bolt aka slider pin. These two needs to be removed, cleaned and properly lubricated with silicone grease. If me I will take everything apart, clean thoroughly, add grease only on slider pins and put all back together. Very important here to check pistons for free return. 

[Red_Corolla]

Another point about the anti rattle shims is that lots of corrosion tends to build up underneath them on the iron bracket. I would always remove those shims as part of any brake service and remove as much rust as possible from the area where they seat before replacing them. It's also a good idea to use new shims when replacing the pads because the old ones will have lost most of their flexibility.

[DerekHa]

On the subject of greasing the slider pins.

Don't make the mistake I did years ago on my son's Mazda 323f! I thought Copper Ease would be fine as it's an anti sieze grease. What I didn't know is that it's petroleum based and it attacked the rubber and made them swell like crazy causing the pads to start sticking on the disc.

Look for either a red brake grease or a one thats silicone based and the sliders and the rubber covers will get along fine.