how worn would discs need to be to fail an MOT?...
 

I've currently got a little Polo GTi which will be due it's MOT in a month or so.

It recently had a new clutch, and the garage tried to get me to get the front discs and pad's changed as they said they were due, but they don't look too bad to be me.

There is some wear on the discs, and they're 'lipped' slightly - ie prob 1mm of wear, so little lips on the edges.

Anyone know got any idea what would be considered too worn to fail the MOT???

Thanks :)

I've always known it as 2mm lip is the limit

They use digital callipers and they use a maximum run off, something like 0.6mm for disks and 1.6mm left for pads.

I think, from the last time I went.

disc s will have wear indicators on them ie flat edge on outer radius .......

:D i am an MOT tester , you cannot fail a disc on been to worn , it is simply impossible as all manufacturs specifie different thicknesses and there is no way of measuring thickness of a disc with the wheel on (on most cars ) so you just dont test it you can fail a disc on excessive corrosion ie if 2/3 of the disc is pitted os excessive scoreing which dont really happen or u can fail it on cracks, but thats it definatly not on thickness however the brake pads must have atleast 1.5mm of friction materel left on them hope this helps ;)

Depends on the MOT guy; some will fail you on any amount of lip... (pitted)

Don't get me wrong, I know I was:cool: , its just the amount of wrong that I was wrong that makes me look....:sleep:

if they fail it on a lip apeal against it as u cannot do so only on pitting of the disc surface

Thanks guys :)

I've just had second look at them, and I reckon I'll chance it as the lip is not that bad really, probably nearer 0.5mm, and the pads look pretty new.

Does seem like a slightly grey are though really.

check the inside surface of the disc as that is where its most likely to corrode people often think there brakes are fine because they are shiny on the outside but the inside could be just brown with corrosion:lol1:

dont take it to the garage who advised you for the mot as the likelyhood is they will fail you

For what a pair of discs and a set of pads costs, and the time it takes to swap them, is it not worth replacing them just for the peace of mind :wonder:

Unless of course it's the mother-in-law's car :Suspiciou

As Johno says above, if they do fail the car on that, you can appeal, as they aren't allowed to :nono:

That's what I thought until I tried to get the discs of my 530d... bloody things were not moving for anyone.

You've obviously let your Brute Force & Ignorance qualification lapse :rolleyes:

I bet it was nothing the judicious use of heat, cold, and a Fcuking Big Hammer couldn't have shifted :lol1:

Its a performance car, albeit a little peformance car. Dont skimp on things you need to stop it quickly!