Motoring Discussion > Lipped Discs Miscellaneous
Thread Author: Bromptonaut Replies: 23

 Lipped Discs - Bromptonaut
My 2016 Fabia had its annual service on Thursday. Last service included in the plan that was bundled with the car. Mileage since new c40k.

They've reported it as needing new front discs/pads at a cost of approx £340. The pads are 40% worn (or maybe 40% remaining). Issue is said to be that the discs are 'lipped'. There's a visible lip on the outer circumference of the outboard face - visible through the alloy wheel - of perhaps 1.5-2mm. Bit less at the inner edge of the pad. I suspect corrosion has bulked the outer lip.

The discs themselves are in two parts with a heat sink in between. Very similar or perhaps identical (VAG parts) to those shown here:

www.seat.com/car-terms/v/ventilated-disc-brakes

There's still loads of metal on either side of the heat sink. The service report says nothing about the remaining thickness of the discs or what the permitted wear might be.

What does the panel think?

I suspect owner #1 was heavy on the brakes and we're on the original discs and second set of pads.
 Lipped Discs - neiltoo
What did the MOT say?
 Lipped Discs - Bromptonaut
Passed the MoT a week earlier at a different place.

Obviously that checked brake effectiveness and balance but the wheels stayed on and, watching from the viewing area, I didn't see the discs get any attention.
 Lipped Discs - MD
I'm sure I've posted this yonks ago? However when I bought my First Renault Master new in 2002. Two things happened. At one of the services whilst still under warranty they changed the brake pads, because they only had perhaps 30% left on them and in their words they wouldn't last until the next service. I said that I'm capable of thinking for myself and changing them myself so just put them back on as I'm not paying for anything I haven't asked for. They said they're in the bin and gone, so I said tough *itty you'll not be paid.

This bit gets me. At the FIRST MOT they stated that the rear lenses were worn and were showing too much white light and new would have to be fitted. I mentioned something akin to Foreign Office. Funnily enough it passed. It had the same lenses when I sold it 16 years later. The motor trade is beyond ruddy bent.
 Lipped Discs - bathtub tom
They're not in two pieces, they're cast in one piece.

If you search the internet, you'll find the minimum permissable thicknes of the discs (mine have it moulded into the casting), you'll probably need some calipers to measure them.

All discs show a lip once the brakes are used (the disc wears as well as the pads).

They may well be 'trying it on'. Get the discs measured and ignore 'we don't know how many miles you do a year sir'.
 Lipped Discs - sooty123
Go on euro car parts, it will tell you the minimum thickness for the discs.

Although I'd be surprised if a city car like that had worn through a set of discs in 40k.
 Lipped Discs - Zero
My indie skimmed the lip off my disks as they met the minimum thickness spec. 60 quid for both disks.

Set of disks/pads for a 2016 fabia diesel, about 80 quid per axle.
 Lipped Discs - carmalade
Any car that is used will get lipped discs , as the pad coverage doesn’t extend to the edge of the metal . Drive on and don’t worry about it .
 Lipped Discs - Kevin
As carmalade says, they all do it. I'd be more concerned if there wasn't a lip on discs that have been on the car for a few thousand miles.

The discs will have their minimum thickness cast or stamped onto them and the pads should have a wear indicator (sometimes just a piece of metal that touches the disc and squeals when you touch the brakes).

I ordered new front discs and pads for my Chevy a few weeks ago.

PS AR8250EVC Rotors...£70.54
Bosch BE413H Pads......£17.20
FedEx Int. Priority...........£122.55
Duty & VAT......................£45.09
 Lipped Discs - Fullchat
Everything has been said. I take the lip off with an angle grinder fitted with a flap disc. But thats just me :)

As regards pricing Eurocarparts. Put in your reg number and find the discs and pads (discs are priced as single units. You will get a few options of manufacturer and prices. I tend to go with Pagid which are at the top end of pricing as they produce OEM stuff and there discs have a protective paint finish on the non contact areas :)

Just make sure they are having one of their many sales and get a discount code which is sometimes factored in to the price. They gave more sales than SCS.

If you're using a main dealer its a money spinner for them and its the first go to for emptying customers pockets.

30K miles is not a bad time to have all brakes components stripped and cleaned as they start to stick a bit with corrosion particularly if you are not a high mileage user.
Last edited by: Fullchat on Sat 29 Oct 22 at 20:09
 Lipped Discs - Bill Payer
I've always thought it a bit odd that discs might be something like 22mm thick when new but the spec typically allows for only a mm or so of wear each side - it's like buying tyres new at 7mm and changing them at 6.

OK, I know they have to be designed to cope with braking a fully loaded car towing a carvan down the Alps etc, but it seems a remarkably marginal amount of wear to be allowed.
 Lipped Discs - Biggles
It's not 20 mm of cast iron though. Each side has a thickness of, say, 6 mm so you are wearing a significant proportion of that. Also, what is the maximum travel of the pads?
 Lipped Discs - Bill Payer
Quick Google shows a Fabia ventilated disc (not necessarily same as OPs) as approx 8mm each side and 9mm vent - 25mm overall and the wear allowed is 1.5mm each side, so 22mm overall.

I'm not saying there's anything wrong with this, just that it doesn't seem much wear from new to worn out. It's become routine to change pads and discs at the same anyway now, so it's probably mostly irrelevant.

The pads will travel the thickness of the material (and more if you ignored the noise) - probably 8mm ish?
 Lipped Discs - bathtub tom
>> It's not 20 mm of cast iron though. Each side has a thickness of, say,
>> 6 mm so you are wearing a significant proportion of that. Also, what is the
>> maximum travel of the pads?

I experienced that, when I bought a car that I susbsequently found to have had its discs skimmed. Travelling at speed down the A2 to a roundabout, the brake pedal hit the floor.
A caliper piston had come out so far it wedged sideways, causing slight pressure on the pad. The heat generated boiled the brake fluid.
Quick fix in a lay-by was new pads and fluid bleed, about an hour. New discs fitted when I got home.
 Lipped Discs - Terry
I suspect the maximum wear limit is based upon worst case usage of the brakes - eg: used aggressively coming down the St Bernard pass.

But if you are involved in an accident an insurance company may refuse a payout if you have not acted to remedy a safety critical item as advised by a garage.

Also - depending on how long you plan to keep the car - at some point in your ownership you may need to replace them - you may as well do it now as in a years' time.

Price seems a bit over the top for a very simple job - an independent may save £100-150.
 Lipped Discs - VxFan
>> Everything has been said. I take the lip off with an angle grinder fitted with a flap disc. But thats just me :)

Providing the brake disc is still above min thickness, I just use an angle grinder with the normal cutting disc fitted.
If it's a driving wheel, jack up one corner and remove the wheel. Start car and put in 1st gear. The diff will allow the wheel off the ground to rotate and not bother to rotate the other wheel (unless 4WD and with diff lock on).
Now hold the angle grinder gently onto to the rotating brake disc and remove the lip. This way you'll get it uniform and minimise unbalancing the brake disc.

Repeat for the other side.

You might get the ABS warning light come on, but it should go off again once you've driven off down the road.
Last edited by: VxFan on Sun 30 Oct 22 at 02:44
 Lipped Discs - sooty123
Why are the lips on the discs being ground off, unless the pads are catching them?
 Lipped Discs - VxFan
>> Why are the lips on the discs being ground off, unless the pads are catching them?

Not sure if other manufacturers have this, but Vauxhall use an audible warning system when the brake pads are getting low, which basically consists of a thin piece of metal sticking out the side of the pad and when the pad has worn down, the metal touches the disk and makes a squealing sound.

The lip can prematurely set off the low brake pad warning if not ground off.

pmmonline.co.uk/wp-content/uploads/2017/08/Wear-indicator-copy.jpg
Last edited by: VxFan on Mon 31 Oct 22 at 13:28
 Lipped Discs - Bromptonaut
>> Although I'd be surprised if a city car like that had worn through a set
>> of discs in 40k.


Do you mean a relatively light weight car?

I'd expect a city car used as such, mostly stop start around town, to exhibit more brake wear than a vehicle used long distance. The Fabia got little use in 20/21 due to the pandemic but this year its been up and down to Liverpool/NE Wales to see the offspring and to the Western Isles and back.

It's an estate so has a huge boot for a city car. The cost of that is very tight seating in the back but as we're only using it for two of us that's a non issue.
 Lipped Discs - Lygonos
When I started driving in the 80s you'd typically go through 3 sets of pads before the discs needed replaced, now I change the discs and pads at the same time as they seem to wear together.

Not sure if this is because the discs are "softer" or the pads more hard-wearing, or because cars are ~50% heavier than back then and the discs suck up more heat, or a bit of all 3.

Lipping is largely irrelevant other than being an indication of disc wear - as noted above actual disc thickness is the important factor.
 Lipped Discs - tyrednemotional
>>
>> Not sure if this is because the discs are "softer" or the pads more hard-wearing,
>> or because cars are ~50% heavier than back then and the discs suck up more
>> heat, or a bit of all 3.
>>

The use of asbestos in brake/clutch friction material was largely banned in 1999,(and was being phased out before that).

As a result, pads/shoes were made of harder materials, and disc wear, (they remained as per previous material), became more prevalent.

My perception is that, before this date you were probably more likely to replace discs due to warping than due to wear.
 Lipped Discs - sooty123
Do you mean a relatively light weight car?
>>

Yes.

The Fabia got little use in
>> 20/21 due to the pandemic but this year its been up and down to Liverpool/NE
>> Wales to see the offspring and to the Western Isles and back.

Even less likely then.

Without seeing them, I'd guess it's some easy money for the garage.
 Lipped Discs - Dave_
I was working at an MoT station recently. Lipped discs would be an advisory, we would recommend the customer budgets for a replacement pair of discs at the next brake pad change. No more, no less.
 Lipped Discs - Lygonos
You still work at MG at all Dave_?

The discs were a bit crappy on my 69-plate ZS - grooving, glazing and corrosion all at work!

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