[Zhouzian]

During the maintenance work, dealer suggested to re-surface or change rotor due to inside corrosion. I wasn't sure if the dealer was just bs or not, so wanted to hear suggestions from the forum. I asked dealer to send me both front and rear rotor from inside.

[mmm-five]

Are you sure you've got the right size pads/calipers on, as there seems to be a huge unswept area at the edge of the disc!

I'd simply be replacing them myself (along with new pads and checking the fitment), as resurfacing them may only leave you with 1000 miles of life.

[Zhouzian]

Originally Posted by mmm-five

Are you sure you've got the right size pads/calipers on, as there seems to be a huge unswept area at the edge of the disc!

I'd simply be replacing them myself (along with new pads and checking the fitment), as resurfacing them may only leave you with 1000 miles of life.

The rotors and pads were installed from the factory and never removed. Maybe it was not installed correctly from the factory? I do not feel anything wrong when breaking though.

[Ennoch]

Inner faces almost always corrode like that in salty/damp environments. Depends on what the wear is like and how much material would need to be removed to get them down to a decent surface (how much good steel rather than the rust as that'll be fatter than the disc was when new!). Anything more than 0.5mm and I'd be going for new rotors. If that takes them to more than 60% worn then I wouldn't bother and just replace them. The only exception I've really applied to this in the past has been for low mileage 'fun' cars where the remaining metal will still give many years of use, where the discs are difficult to get hold of (some obscure seventies Citreon), or where the rotors are massively expensive and thus the cost of skimming them to get an extra 10k is still worthwhile over buying new.

Are they the two piece aluminium set up with the grey m-sport calipers, or are the discs one piece? If they're one piece then I'd just replace them as they won't be that expensive. If they're the aluminium centred ones then double check what they're worn to at the moment and make a decision from there based on what life you'll be left with once skimmed. Another point to consider here is that once skimmed you'll need new pads. If you're not going to get a great distance from them once skimmed then the cost of the new pads being binned while still 70% good further pushes the argument in the direction of just fitting new discs.

[Billfitz]

If you're having the dealer do the work (probably a mistake, but that's a different question) it may not cost much more to get new rotors, given the absurd cost of labor. Doing it yourself it would be a simple matter to remove that rust. A full resurfacing is only necessary if the contact area of the rotor is scored, which yours are not. You didn't mention if the pads are being changed. If not you don't need to do anything at this point.

[Zhouzian]

Originally Posted by Billfitz

If you're having the dealer do the work (probably a mistake, but that's a different question) it may not cost much more to get new rotors, given the absurd cost of labor. Doing it yourself it would be a simple matter to remove that rust. A full resurfacing is only necessary if the contact area of the rotor is scored, which yours are not. You didn't mention if the pads are being changed. If not you don't need to do anything at this point.

The pads were never changed. Then I'll just leave it as is. Thank you for the suggestions.