My son came home today in his focus sport tdci, and told me the front nearside wheel was making a grinding noise when braking. We checked his brake pads had plenty of material remaining (2-3mm), and the disks looked ok. But it still doing it. What might be the problem ?
2mm is not "plenty". It's going to need new pads very soon, so change them now and see if the noise disappears. Chances are it will.
Whilst you are doing it, measure the disk thickness remaining. They usually need replacing every other set of pads.
Chris
Do these pads have wear sensors? That's the 10mm strip of metal wrapping around, riveted off the back of the pad. This scraps the rotor and makes the noise.
If the pads have 2-3mm of material left this is when the sensors kick in.
Pads don't perform when down at this level anyway they get hot and fade.
ford pads just go down to metal: no audible wear sensor, but they often wear unevenly, so one edge may have 3 mm the other nothing, some models even have different friction material on each pad. the only way to know is to take them out. discs and pads are so cheap and easy on a focus it is not worth messing about, just change the lot.
We had decided to go this route since they will need doing soon anyway. Hopefully this will clear it. I had a quick question re changing the pads. On most cars I've compressed the caliper piston back, removing the cap on the master cylinder to make room for the fluid that is being forced out of the caliper. But I have seen some comments saying this can flip the seals on the master cylinder so the brakes no longer work so you should clamp the flexi hose back to the master cylinder and bleed the excess hydraulic fluid at the nipple on the caliper ? Is this really necessary ?
On Mon, 04 Jul 2011 09:50:58 +0100, Tonyb wrote: [...]
Desirable on any car, necessary if ABS fitted.
A good tip from Mr C recently was that after changing pads you need to press the brake pedal a few times to get everything back in place, and the pedal could go to the floor. There is a risk that this could damage master cylinder seals, so rather than push the pedal all the way down, do it in a greater number of shorter strokes, using the amount of travel that would be normal.
Chris
FYI, Pads and disks replaced. When we stripped out the old pads/disks, we found one Inside pad worn down to metal, although outer pad had 4-5mm remaining. Everything looks (and sounds) good now. Thanks for all advice.
These calipers have one piston and rely on the slide of the caliper to equalize the pad wear. Obviously they were not working correctly as indicated by the pad wear.
Did they do any service like lubricate or clean the slide mechanism?
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.