Thoughts on condition of brake disc help please!
Discussion
Okay so I have some good knowledge with mechanics and car but it's been noted as an advisory that my brake discs are worn and pitted when I had it MOT'ed and then a few months later I had to have a tyre replaced and they also commented on the condition of the brake discs saying exactly the same thing.
I decided to have a look at my brakes and removed a disc to inspect it properly but I cannot see what on earth these people are talking about. The brake disc is only worn slightly and as far as the pitting goes there isn't any really apart from the edges where the brake pad doesn't touch. Also the pads themselves have a substantial bit of material left on them so they're fine too.
Does anyone on here agree with them and recommend I renew my brake discs??
I decided to have a look at my brakes and removed a disc to inspect it properly but I cannot see what on earth these people are talking about. The brake disc is only worn slightly and as far as the pitting goes there isn't any really apart from the edges where the brake pad doesn't touch. Also the pads themselves have a substantial bit of material left on them so they're fine too.
Does anyone on here agree with them and recommend I renew my brake discs??

did you measure the disc thickness?
it look like the brakes are pretty old and have been on the car a while, they look from this angle like they are non vented, so possibly rear discs.
Discs are cheap, and an easy install job, for the effort you've take to remove them you could have just put on a couple of new discs for probably £20-£30.
At the end of the day, it's your car, if the brakes fail, it no big deal.. you should be able to use the car ahead to slow you down.
So just crack on I'd say.
it look like the brakes are pretty old and have been on the car a while, they look from this angle like they are non vented, so possibly rear discs.
Discs are cheap, and an easy install job, for the effort you've take to remove them you could have just put on a couple of new discs for probably £20-£30.
At the end of the day, it's your car, if the brakes fail, it no big deal.. you should be able to use the car ahead to slow you down.
So just crack on I'd say.
The reason everyone is commenting on the condition of your disks is
1. Brakes scare people and they are likely to just get them replaced because they think they will die.
2. Brakes are easy to change and will make the garage owner easy money.
3. People don't understand how to judge the condition of their brakes.
Yours look OK to me, it would be easier to judge if you took a photo at an angle showing any lip around the edge.
1. Brakes scare people and they are likely to just get them replaced because they think they will die.
2. Brakes are easy to change and will make the garage owner easy money.
3. People don't understand how to judge the condition of their brakes.
Yours look OK to me, it would be easier to judge if you took a photo at an angle showing any lip around the edge.
Looking at the picture, it does look exactly as they've said on the advisory..."worn and pitted" (you can see the lip on disc, the scoring and the pitting).
But it's just an advisory, so it's still roadworthy and passed the test, so don't worry.
Don't forget, the moment you fit something and use it the first time, it becomes 'worn'...the same language that dealers use when they want to upsell you on new tyres/brakes during a routine service.
But it's just an advisory, so it's still roadworthy and passed the test, so don't worry.
Don't forget, the moment you fit something and use it the first time, it becomes 'worn'...the same language that dealers use when they want to upsell you on new tyres/brakes during a routine service.
Thanks everyone for your time, input and advice. I thought the same that they really aren't that bad as they've made out. These are the rear brake discs and as someone mentioned I forgot to take a photo on an angle to show edge but I think If I had you would still be giving the same advice about them looking pretty good.
I know these garages are probably banking on people being none the wiser and end up getting parts renewed went they don't necessarily need to be but say it just to get some more dosh out of you, naughty really!
I understand of course that brakes are quite important but this car isn't a Ferrari or some sort of racing car lol
I think I could just clean them up with a flapp disc grinding pad and they'll be good for another year or so to be honest.
The one thing I didn't do was measure the thickness but as I said there isn't that much wear on them. I am not sure what the recommended minimum thickness is on a single disc? I believe the minimum thickness on a double layer disc is 21mm but not sure bout a single, does anyone know??
I know these garages are probably banking on people being none the wiser and end up getting parts renewed went they don't necessarily need to be but say it just to get some more dosh out of you, naughty really!
I understand of course that brakes are quite important but this car isn't a Ferrari or some sort of racing car lol
I think I could just clean them up with a flapp disc grinding pad and they'll be good for another year or so to be honest.
The one thing I didn't do was measure the thickness but as I said there isn't that much wear on them. I am not sure what the recommended minimum thickness is on a single disc? I believe the minimum thickness on a double layer disc is 21mm but not sure bout a single, does anyone know??
Difficult to exactly estimate measurements from a picture, but that disc has got a 1cm odd band of corrosion/pitting around the outer edge of the contact surface, that will be cutting through the pad.
Without knowing the characteristics of the car’s braking system, I’d say it would be unusual to have a correctly fitted pad (and one that is correct for the car) that doesn’t contact the entire friction surface of the disc in operation.
It’ll still work, but not at its best. I can see why the MOT tester advised it; I’d have done the same. He’s not failed it-only advised, probably covering his backside from those that would moan when he didn’t tell them.
Without knowing the characteristics of the car’s braking system, I’d say it would be unusual to have a correctly fitted pad (and one that is correct for the car) that doesn’t contact the entire friction surface of the disc in operation.
It’ll still work, but not at its best. I can see why the MOT tester advised it; I’d have done the same. He’s not failed it-only advised, probably covering his backside from those that would moan when he didn’t tell them.
itcaptainslow said:
Difficult to exactly estimate measurements from a picture, but that disc has got a 1cm odd band of corrosion/pitting around the outer edge of the contact surface, that will be cutting through the pad.
Without knowing the characteristics of the car’s braking system, I’d say it would be unusual to have a correctly fitted pad (and one that is correct for the car) that doesn’t contact the entire friction surface of the disc in operation.
It’ll still work, but not at its best. I can see why the MOT tester advised it; I’d have done the same. He’s not failed it-only advised, probably covering his backside from those that would moan when he didn’t tell them.
Thanks. Yeh it does have have that roughly 1cm band around the edge and if I was going to fit brand new pads it might warrant changing the discs as well but as the pads have plenty of life in them I think I will as you say you do just grind the edge of, clean up everything with some brake cleaner and reapply some copper grease to the contact parts of the existing pads etc and I reckon when it comes to it's next MOT they won't even mention anything about them...Without knowing the characteristics of the car’s braking system, I’d say it would be unusual to have a correctly fitted pad (and one that is correct for the car) that doesn’t contact the entire friction surface of the disc in operation.
It’ll still work, but not at its best. I can see why the MOT tester advised it; I’d have done the same. He’s not failed it-only advised, probably covering his backside from those that would moan when he didn’t tell them.
It would absolutely warrant changing the discs-they’d ruin the new pads instantly. As you say though-I’d clean everything up (including the caliper slide pins-could be a reason why the pad isn’t contacting correctly), resurface the pads with rough emery paper, and try to remove as much of the disc lip/pitting as possible.
P.S. do not use copper grease on brake friction parts that need to move-use proper brake grease, available from motor factors. Copper grease dries out and goes sticky!
P.S. do not use copper grease on brake friction parts that need to move-use proper brake grease, available from motor factors. Copper grease dries out and goes sticky!
itcaptainslow said:
It would absolutely warrant changing the discs-they’d ruin the new pads instantly. As you say though-I’d clean everything up (including the caliper slide pins-could be a reason why the pad isn’t contacting correctly), resurface the pads with rough emery paper, and try to remove as much of the disc lip/pitting as possible.
P.S. do not use copper grease on brake friction parts that need to move-use proper brake grease, available from motor factors. Copper grease dries out and goes sticky!
Okay thanks and sounds like good advice with the grease...P.S. do not use copper grease on brake friction parts that need to move-use proper brake grease, available from motor factors. Copper grease dries out and goes sticky!
PhillipM said:
That outer edge looks like it's where the pad should run - and it's ground the pad away to shape, so I can see why. If it was me that would be new discs and new pads time. That's the kind of issue that causes odd vibrations occassionally and inconsistant pedal feel.
I don't think there is any brake pad that goes all the way to the edge, I've think you'll always get a lip left behind from wear on any car.Worn & pitted does describe the disc surface in that pic, but to what extent & whether it is enough to seriously affect braking performance I can't tell.
Hard to tell 100% from the pics but it looks like the rust build up on the outer edge of the disc is now starting to be worn by the disc backing plate possibly indicating there not being much pad left.
If it were my car considering the price of the parts & the relatively short easy job, I would be changing discs & pads if that is indicative of the condition generally of all.
Of course, I am only commenting on the one pic of one side of one disc, there is a lot more braking real-estate on the car that could change that opinion.
Hard to tell 100% from the pics but it looks like the rust build up on the outer edge of the disc is now starting to be worn by the disc backing plate possibly indicating there not being much pad left.
If it were my car considering the price of the parts & the relatively short easy job, I would be changing discs & pads if that is indicative of the condition generally of all.
Of course, I am only commenting on the one pic of one side of one disc, there is a lot more braking real-estate on the car that could change that opinion.
dilligaf76 said:
I don't think there is any brake pad that goes all the way to the edge, I've think you'll always get a lip left behind from wear on any car.
On most cars yes, but you can see from the polished top on that that it's been brushed by the pad and probably chewing the pad - did you pop the pads out, do they have a matching groove?Gassing Station | Suspension, Brakes & Tyres | Top of Page | What's New | My Stuff