brake pads not sitting fully

[eibrahim]

can anyone please tell me whats wrong with these brakes ? pads only touching half the disc surface ,its only on one side , do i need to be worried ?

Edited by eibrahim on Monday 13th March 17:40

[buggalugs]

It can happen if the car or rear brakes are only lightly used, corrosion creeps in from the edges and wears the pad in those areas. You would want discs and pads replaced to fix that. However I'm not sure if that's an MOT fail as long as they pass the brake test in which case you might choose to live with it.

[stevieturbo]

Wouldn't be overly worried.

Could be a sticky caliper, or just very infrequent use and lots of sitting about.

But at some point yes it will need remedied.

[eibrahim]

buggalugs said:

It can happen if the car or rear brakes are only lightly used, corrosion creeps in from the edges and wears the pad in those areas. You would want discs and pads replaced to fix that. However I'm not sure if that's an MOT fail as long as they pass the brake test in which case you might choose to live with it.

its only on rear passenger side , driver side is normal

[TooLateForAName]

I'd be replacing the discs and pads and making sure that the caliper carrier /pad sliders were cleaned up and cleaning/lubing the slider pins.

[donkmeister]

TooLateForAName said:

I'd be replacing the discs and pads and making sure that the caliper carrier /pad sliders were cleaned up and cleaning/lubing the slider pins.

This.

OP, if you DIY it then make sure to use red rubber grease to lube the sliders.

If it comes back then you will need to rebuild/replace the caliper (not usually as bad as it sounds, unless you drive something rare).

[F355GTS]

Seen this where the pads have locating pins on the back and locating slots in the piston and these are not aligned

[Smint]

TooLateForAName said:

I'd be replacing the discs and pads and making sure that the caliper carrier /pad sliders were cleaned up and cleaning/lubing the slider pins.

Agreed, apart from anything my OCD would kick in and those unswept rusty disc sections might as well be luminous.

Something's been sticking even if its not currently to end up with only half the disc clean.

Don't forget to exercise the piston(s) in its bore several times, its permissable to peel the duist cover back and apply some of the correct brake grease to the piston itself whilst its out, judge for yourself how much pressure is required to push the piston back in.
Also ping off those stainless spring clips that the pads sit in and clean everything up, judging by the state of the disc/caliper rust there will be a build up of rust/crud under those clips making the pads a tighter fit than they should be.

Edited by Smint on Tuesday 14th March 08:19

[E-bmw]

TooLateForAName said:

I'd be replacing the discs and pads and making sure that the caliper carrier /pad sliders were cleaned up and cleaning/lubing the slider pins.

^^^ Wot 'e said.

While braking performance may not be hugely affected by just this there may well be other issues, never mess with brakes, they need to be perfect.