"NY" wrote in message
o.uk...
"dennis@home" wrote in message
b.com...
The biggest problem is if the pads wear down to the rivets that fasten
them to the backing plates, because the rivets can there score the
discs,


I haven't seen pads with rivets for years.

I believe it has been law for many years that cars have a warning system
to show worn pads. Its used to be a copper stud set into the pad
connected to a wire that shorts to the disk and lights a lamp.
Mine is indicated by the computer but I expect its still a copper stud.
The biggest failure mode is the wire falling off the pad.


Could it be the copper stud embedded in the pad that causes the scoring of
the disc in the same way that (in the olden days) rivets would do.

I checked the warning light when I experienced the symptom, knowing about
brake pad warning wires/studs, and the light (the same one as used for
handbrake-on) did not light, so it may be that the wire had fallen off
since the last time the brakes have been checked and passed for another X
thousand miles.

I'm intrigued that a lot of people have done large mileages without
needing new discs,

I'm not, because I know its because I dont use the brakes that much.

because on all the cars that I have had, brake discs tend to be needed
roughly every three times that the pads need changing.

But when you only change the pads once in 45 years,
its hardly surprising that the discs are still fine.

And that's with fairly gentle progressive braking (ie not rushing up to
lights at 60 and then slamming hard on at the last moment).

I dont normally slow the car at the lights with brakes. I do usually
apply the brakes just at the end so the car doesnt drift forwards
or backwards while waiting for the lights to change, but that
obviously doesnt wear the brake pads any.

I presume it makes a difference if you live in hilly country:

Not with me. I hardly ever use the brakes in hilly country
except when actually pulling to a stop before applying
the handbrake after I have stopped.

even with engine braking to take some of the braking load, you will still
use your brakes more than if you live in flat terrain.

I dont.

Mind you, modern learners are taught not to use engine braking on a long
hill, but to stay in a fairly high gear and rely entirely on brakes -
that's what my nephew said he was told, anyway.

I do very little engine braking in the sense
of changing down a gear in hilly country.

I wouldn't like to descend Porlock Hill, Rosedale Chimney or Park Rash
using only my brakes, without going down into maybe third or second to
give at least *some* engine braking.

Sure, but there arent to many that do a hill like that daily or weekly.