Lol guy. 275/75-18 is not going to fit in any sense of the word without major mods. None of which include the rods. You will not be able to actually move at all Rukeyser if you ever have s suspension fault. Meaning even on pavement. I have done a ton of work to fit 32” as well as 34” but it’s a much bigger commitment. To others asking, 265/65-18 fits fine in spare location at full inflation. You might just need to remove the fiberous shield between it and exhaust or just stuff it in there right.