Why are tyres for my Vauxhall Insignia so expensive?

I retired in 2011 and purchased my 2009 2.0-litre diesel automatic Vauxhall Insignia Elite company car from my employer. It has now covered around 33,000 miles and is in need of new tyres (245/45 R18 96W). After making a few enquiries I was shocked to learn that new replacement tyres will cost around £250 each (£1000 for a set of four). I cannot understand why the price of these tyres are so high when a replacement tyre for an equivalent Ford Mondeo would cost around £120. I am concerned that in a few years time the tyres will be more valuable than the car.

Asked on 28 September 2013 by CC, via email

Answered by Honest John
Dump the stupid 18-inch bling wheels that an Insignia simply does not need. Get in touch with www.tyremen.co.uk who will sell you a set of TUV-approved 16-inch Alutec alloy wheels for £335 inc. Then buy a set of 205/55 R16 tyres for them (Tyremen can supply and fit). Then 'disclose' the 'modification' to your insurer. The car will ride much better and be less susceptible to pothole damage.
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