Garage says brakes are rusty and need cleaned due to lack of driving. Is this right?

My daughter in law took her Mazda MX-5 for a service this week. It's about eighteen months old and she has had it since June 2020. Due to lockdown, though, she's not driven too much.
The dealer rang her to say that there is a build-up of rust on the brake discs and, whilst not dangerous, they could do with skimming/cleaning to remove the build-up at a cost of £260. Should anything like this have been picked up before she bought it? Is this also likely to be true of most cars which are not driving as much as normal? Thank you.

Asked on 2 February 2021 by John Roberts

Answered by Keith Moody
It's very common that cars which don't get much use do see a build-up of slight surface rust on the brake discs. This of course reduces the car's braking efficiency, but I wouldn't expect the build-up to be so bad that the discs need cleaning. A good run with lots of regular, gentle braking should do the trick and clean them up.
Tags: rust
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