I am thinking about going up in size from the OE 275/55/20 (31.9"). to a 275/65/20 (34.1"). I am most likely going to go with a Goodyear Wrangler All Terrain as I do primarily city driving. Does anyone know how it will affect mileage and towing? and I am assuming the ride should be a little softer due to the taller sidewall?