I switched to 235/45/18s on my 2019 Touring right away. I wanted aftermarket wheels (BBS) and a bit more sidewall for a bit more comfort. The circumference is the same as the stock 235/40/19s so there's no change in the speedometer reading, etc. Since the wheel is smaller and lighter I believe I even got increased MPG out of the swap. I now have 70k on the odometer and I'm very pleased.