The 2005 Impala was the last of its generation, and therefore saw few changes. Among these changes was that OnStar was now a standard feature on all trims, a popular enhancement among Impala drivers. Engines remained the same: a 3.4-liter, 180 horsepower V6 for the standard sedan, a 3.8-liter, 200-horsepower V6 for the LS, and a 3.8-liter, 240horsepower V6 for the SS. Drivers love the solid handling, rapid acceleration, and all-over peppy drive. Some have complained that the car does not approach is estimated 21 city/32 highway mileage (20/30 and 18/28 for the LS and SS), yet many seemed pleased with the efficient gas mileage accompanying the strong engine. All trims now come standard with driver, passenger, and side airbags, creating a safe environment for the up to six passengers inside the car.