Why do you recommend fitting winter tyres onto spare wheels for my Volvo V40?

I have followed your advice on winter tyres, which have transformed my 7-year-old Volvo V40 in the snow and ice. I thank you, but please could you explain why you advise winter tyres 'on a separate set of rims'. Is it simply to save the cost of having the tyres changed twice a year? If so, this must be offset against the cost of new rims, which is significant if I shall be selling the car in the next two years. I have substituted the 'normal' tyres, which now sit in the garage, for exactly the same size in 'winter tyre', and the (national) tyre fitters assure me that this is acceptable, and not a change in specification.

Asked on 6 December 2010 by JG, via email

Answered by Honest John
Firstly it gives you the option to switch from blingy big wheels with low profile tyres to smaller wheels with deeper profile winter tyres that will be more effective in winter. Secondly, if you swap to steels, it prevents your expensive alloys getting damaged by saline grit. Thirdly it prevents damage to the tyres and rims from having them swapped twice a year, and also reduces the cost. If you switch to steels you will probably need different, shouldered wheel nuts or bolts. You have to tell your insurer, but, sensibly, the ABI has ruled this is not a ‘modification’ subject to a premium increase.
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