Disappearing break pad

poker_999

poker_999

poker_999

Permabanned
Joined
25 Jan 2012
Posts
508
hi a few days ago my breaks started grinding so I bought some new pads.

I was fitting them today and was absolutely amazed to find only 1 break pad in the calliper and the piston had been rubbing against the back of the rotor.

How on earth is it possible for a break pad to fall out from a calliper assembly?
 
You've worn the pad away so much the lining has gone, then the metal backing has started to wear, then that's worn away so much its dropped out of the caliper.

Lucky you were able to stop, much more and the piston would have come right out.
 
Zack101 said:
You've worn the pad away so much the lining has gone, then the metal backing has started to wear, then that's worn away so much its dropped out of the caliper.

Lucky you were able to stop, much more and the piston would have come right out.
Click to expand...

That sounds plausible but highly unlikely as the car drove so well prior to the noise of the piston rubbing against the rotor which was the first indication that anything was wrong at all with the brakes
 
Yeah well unlikely or not that's what happened. When the noise started what makes you think that was the piston on the disk and not the metal backing of the brake pad?
 
There have been some instances reported of pads having manufacturing defects whereby the friction material can separate away from the back plate and fall out, closely followed a very short time later by the back plate itself resulting in a completely missing brake pad. Age of the components apparently has no bearing on this, it's been known to happen to completely new brake pads only recently fitted. Uncommon but not impossible.

That said, doesn't sound like the above applies in the OP's situation.
 
my brother had the friction material drop off a halfords brake pad before and before he could limp it home the backing plate dropped out too

he didnt loose the piston though, but i didnt see how far it had extended
 
What car is this on? On my E36 there is no way the pad could 'fall out' due to the way it's surrounded by the caliper.
 
Zack101 said:
Yeah well unlikely or not that's what happened. When the noise started what makes you think that was the piston on the disk and not the metal backing of the brake pad?
Click to expand...

because of the way the piston has scored the disk and the noise hadnt changed at all it was just making the noise one day. I would have thought it would have made a different noise on a frictionless pad and a different noise on the rotor disc but it was a consistently same noise
 
I lost all the friction material off one pad. It was on track though.

IMAG0102.jpg


The back plate of the pad was thick enough to stop it falling out the small gap between the carrier and the disk, but if the gap was larger and the back plate thinner its entirely possible that it could fall out. I imagine it would happen almost immediately after the pad failed too.
 
i assume you have replaced the brake disc also? has the retaining pin for the pads gone missing? its the only way i can think the pad could fall out unless it shatterd into pieces but you would defiantly of noticed that happening!
 
I havent replaced the disc, its a bit scored up but should polish out on the new pads.

all clips were in place, I am totally baffled at how the pad could have fallen out
 
poker_999 said:
because of the way the piston has scored the disk and the noise hadnt changed at all it was just making the noise one day. I would have thought it would have made a different noise on a frictionless pad and a different noise on the rotor disc but it was a consistently same noise
Click to expand...

It's all metal to metal. Brake pad metal, piston metal all sound the same from inside the car.
 
poker_999 said:
I havent replaced the disc, its a bit scored up but should polish out on the new pads.

all clips were in place, I am totally baffled at how the pad could have fallen out
Click to expand...

personally i would change its not a fortune for new discs, consider it a chance to upragde to slotted discs to improve your track days?

sounds like it broke apart, but it seems unlikely that you wouldn't notice that :confused:

were you the last person to change the pads on your car? maybe a garage or a mate missed out a pad somehow although that seems unlikely and a stupid mistake
 
You must log in or register to reply here.
Back
Top Bottom