Bigtoe842

Hey all, im new to this site and hoping someone can offer some expertise. I currently have 255/35 19 front tires and 285/30 19 rear tires on a 14 CLS550 4matic. I need more sidewall so i want to go to 255/45 18 front and 285/40 rear. The circumference of the wheels will increase by an inch. How will this affect the drive train? What are my options, if any?