Is it safe to drive with one tyre that's a different aspect ratio?

I have a separate set of wheels and tyres for winter. About two months ago, I damaged a Nokian 255/60 R18 112H XL winter tyre fitted to my Range Rover. My local tyre dealer obtained a replacement and fitted it. They just replaced my winter tyres and wheels, and put my summer ones back on. When I was putting the winter ones away, I noticed that the new one (a Nokian 255/55 R18 109V XL) was smaller than the others. I'm not concerned about the different load and speed ratings, but is it safe to have one tyre with a different aspect ratio?

Asked on 20 April 2018 by Dogman

Answered by Honest John
No, it will damage the drivetrain. Demand that the tyre dealer replaces it with a tyre the correct size.
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