My van takes 225/70/R15 tyres, my mud and snow tyre of choice (to match two already installed) is out of stock and has been for ages.
The tyres I use are pretty much the most off-road orientated tyre I can find that has the correct load and speed rating, the Toyo H09.
There is an alternative 4x4 tyre with a more aggressive (and suitable) tread but to get the load rating needed (112) I need to increase the width, giving me a tyre that is 255 wide, 30mm wider than standard. I would need to get a lower profile to keep the speedo in the right range.
Are there any 'unwritten rules' as to how wide you can go on a given rim width? I have seen sprinters with big off road tyres fitted, and they take the same size tyres as my van, but that doesn't mean its a good idea...
