That is what I put on, is Toyo Open Country AT's, around 800 installed at my local tire shop (local, not one of the big guys). Went from a 260/55 18" to a 255/55 18", and they look sharp. My 2nd row seats no longer vibrate and I don't heard tire noise at highway speeds. Also the LR3 rides nicely with them on too. These would be a perfect fit on the 03-04 Disco SII's with 18's. If anyone wants to take a peek at them, I have them on both rigs now. However the Disco will be upgraded to Open Country MT's some time after the first of the year.
Winslow