Ok I went and got a new tyre fitted yesterday as I got a puncture that couldn't be fixed (gutted as the tyre was nearly new). Had to buy another Bridgestone as I was only replacing the one tyre, now here is where it gets confusing. I have 225/40/R18 92Y on the car at the moment but the guy has fitted a 225/40/R18 92W XL ? I didn't notice this until today so I guess my question is does it really matter that the tyre is one speed rating down and it's an XL (whatever that means)? And if so, can I go back and ask them to change it as I have already left the premises? The car is only a 140 Diesel so I doubt I will be getting anywhere near the 168mph limit of the new tyre.