There have been many threads on this, but i thought I'd share my experience with you.

Changed to 225/45s last year. Didn't know anything about tyres, load ratings etc at the time. The tyres were Goodyear Eagle F1s 91 Y

Found out on here that maybe I should have had XL ones i.e. 94 not 91.

Checked with the tyre fitter, he said no 91s were fine, spoke to VXL who didn't know (said ask the tyre fitter ). Spoke to Goodyear / Dunlop technical who said 91s are OK. Finally got a return call from VXL technical saying 90 are ok not even 91.

Messing about on the net the other day & found this site http://www.mygoodyear.co.uk/

On here it lists 91 load for the HATCH & SALOON V6 CDTI but not for the Estate (which is what I've got) instead it lists the XL tyres only.

Rang Goodyear again. This time they did confirm that the ESTATE required XL. The Hatch / saloon cars must be very close to the limit of the 91s and the Estate (and probably the Signum) due to their longer wheel base & weight, exceed them. Or can exceed them when fully loaded.

I think this might be why we get so much conflicting advise on these tyres.

Back to the fitters, who have agreed to off set a proportion of the value of my old tyres against new XL ones. Fingers crossed.