Drive: Kia's K5 has gorgeous design but a weak fuel economy Steven Macoy FacebookTwitterEmail 1of5 Kia's 2021 K5 GT features a stunning design, but it only has a 26 mpg city, 34 mpg highway fuel economy.Kia Pressroom / Contributed photoShow MoreShow Less 2of5 Kia’s 2021 K5 GT features a stunning design, but it only has a 26 mpg city, 34 mpg highway fuel economy.Kia Pressroom / Contributed photoShow MoreShow Less 3of5 4of5 Kia's 2021 K5 GT features a stunning design, but it only has a 26 mpg city, 34 mpg highway fuel economy.Kia Pressroom / Contributed photoShow MoreShow Less 5of5 The Korean automaker Kia has exhibited over the years a knack for building very nice-looking cars that are priced right and well equipped.