jimmy tire sizes

My mechanic - yeah, my regular guy, just told me yesterday when I got my tires turned inside out, that I couldn’t get anything larger than the stock 235’s. Not a size or two larger, or 265’s either.

No lift kit, no blocks, no shackle extenders, just stock, is what I’ve got, and want to stay with.

But no taller rubber? Even with extended shackles?

Anyone been here, done this?

The vehicle is a 98 jimmy, 4wd.