I have read several wheel and tire fitment questions posted on this forum, with no answers. I have this same issue, a new to me 2013 E550, about to get a Renntech tune, and these stock 255's are already inadequate with stock power. Would like to keep the stock 18's for ride quality, but just get rid of all seasons and go with a max performance Michelin stepping up to 245's in front and a 275 or even 285's in rear for more traction. I have seen a post suggesting the E550 sedan's 9" rear wheel, part number A2124013702 is an option, but it seems like alot of extra offset to go to a 54 from a stock 48. Anyone done this? I would consider AMG 19's, but the cool ones (C63S and E63S) with the center cap that covers the lugs (centerlock look) are very expensive and probably won't fit anyway.
PLEASE, experts, chime in here!