Getting winter tyres, nearly ordered wrong size?!

[SoVW]

I'm going to sound a right noob, but here goes...

My other half has my GTI out at work at the moment so I can't check the tyres that are on now but I know I have 18" rims.

I wanted to order a set of winter tyres and put in my reg to a tyre shop and it came out with 225 / 45 / R17. I guessed I needed R18 and so searched for 225 / 45 / R18 tyres and nearly ordered some.

Then I checked a GTI forum thread about tyres and people were saying they were running 225 / 40 / R18s. So is it 40 I should be going for and not 45?

[Lap]

Yes. My wife's has 18"'s and they are definitely 225/40. I think they have to be extra load too.

[SoVW]

Cheers