With any of the engines, a responsive four-speed automatic is the only transmission offered. Both of the V-6 engines provide perfectly adequate performance for keeping up with traffic, even when fully loaded, but the V-8 in the SS yields exceptionally fast acceleration--with 0-60 mph times of less than six seconds.
The V-8, which is rated 16 mpg city, 24 highway, also comes with an Active Fuel Management system, which helps decrease fuel consumption during coasting and cruising. With the 3.5-liter engine, highway fuel economy ranges up to 29 mpg, while the 3.5- and 3.9-liter engines come with flex-fuel capability to accommodate up to 85 percent ethanol.
LS and LT models come with suspension settings that favor ride quality but provide good handling control, with rack-and-pinion steering, front MacPherson struts, and stabilizer bars front and back, with 16- or 17-inch wheels and tires. On these models the ride is especially quiet and well isolated. To take advantage of the added power from the V-8, the sporty LTZ and high-performance SS model also add larger stabilizer bars, a sportier, so-called FE3 suspension tuning, and W-rated 18-inch performance tires.
The Stabilitrak stability control system is offered on LTZ and SS Impalas, where it might most help to maintain stability and safety with the added power, but it's not available on 3.5-liter models. This year side thorax airbags for front-seat occupants are now standard, and full-length side-curtain airbags provide head protection. Four-wheel anti-lock disc brakes are also included on all Impala models.
The Impala's interior makes the most of available space, with plenty of legroom for front and rear occupants and enough space in back for two adults of nearly any size--three in a pinch--to be comfortable. LATCH child-seat tethers are included in all three rear seating positions. In LTZ and SS models (optional on LT) the rear seat cushions can be flipped forward to reveal a 'hidden' storage compartment, and the seatbacks fold forward to allow a continuous loading space through the trunk. The Impala is also one of the few remaining cars in its class to offer an available front bench seat, to accommodate three across and six people total.
Base LS models of the Impala come with most of the conveniences that buyers expect, including power windows, keyless entry, cruise control, and air conditioning, plus dual-zone manual climate control and a six-speaker CD sound system with XM Satellite Radio. LT models get a number of appearance enhancements, plus a remote start system and cast aluminum wheels. LTZ models are the most luxurious and bring a long list of extras like heated seats, a universal garage door opener, Bluetooth hands-free calling, steering-wheel audio controls, and a Bose eight-speaker sound system. Nuance leather upholstery with French seams is also included. All sound systems now have an auxiliary input jack for other sources such as iPods.
Many of the LTZ features are also offered as options on the LT. The options list on the top LTZ is quite short, with a dual-screen rear DVD system and a sunroof being the only significant choices.