C7 Rotor wearing on 1 side

C7 Rotor wearing on 1 side

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Vetpork

Original Poster:

6 posts

43 months

Thursday 16th September 2021
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Hi anybody any ideas about this , its just the one Rotor, front drivers side, its the same thickness 28mm all round, so not really wearing

just the grooves have disapeared.

Edited by Vetpork on Thursday 16th September 09:15


Edit.....the discs new are 30mm and the grooves are 2mm deep.....discs need replacing at 26mm...answered my own question

Edited by Vetpork on Thursday 16th September 09:23

mfp4073

1,984 posts

181 months

Thursday 16th September 2021
quotequote all
I'm no mechanic but here's a few free checks to start with,
Take the car out for a gentle drive and try not to use the brakes or at least go easy on them.
Check to see if the car is pulling to one side ( both hands slightly off the wheel ) If it pulls over to the side of the worn disc that's probably going to be sticking pads.
Stop the car and very "Carefully" touch both front brake calipers to see if one is hotter than the other ( the one with worn disc may be very hot! ) again the pads are sticking.
I would remove the pads and press the pistons back into the caliper bores to fee them off.
You also need to thoroughly clean the hub mating surface to make sure there is no rust or dirt which could stop the disc from sitting true. Don't forget to do the same to the rear of the disc.
There should be a slight drag of the disc as you rotate it through the caliper.
One other possible cause is a damaged brake hose. You can check this by opening a bleed valve on the caliper to see if it frees off. If it does replace the hose.

I hope that gives you an idea.

John



Edited by mfp4073 on Thursday 16th September 16:28

stevieturbo

17,525 posts

254 months

Thursday 16th September 2021
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were all the grooves the same depth from new ?

It seems unlikely a disc could wear so much in one spot, and not feel horrific at the pedal.

Lincsls1

3,478 posts

147 months

Thursday 16th September 2021
quotequote all
If the car brakes normally as it were, and the disc is 28mm all over, I'd say its simply a manufacturing defect of the one disc.
Its like the grooves were never evenly deep from the off across the disc.
If it still drives fine, I wouldn't be worrying about it although visually it would drive me nuts and I'd choose to replace.

Vetpork

Original Poster:

6 posts

43 months

Friday 17th September 2021
quotequote all
Thanks for all your replies it drives and brakes just fine.....all the better as i have just changed to Dot 4 brake fluid....but as LincsLS1 has said it will drive me nuts visually....i think new discs and pads is a job for the beginning of next year