- Smooth, responsive performance
- high-quality interior
- available all-wheel drive
The STS comes with either a 302-hp, 3.6-liter, direct-injected V6 or a 320-hp, 4.6-liter V8. Either way, a 6-speed automatic transmission and rear-wheel drive are standard, though all-wheel drive is available. ABS and StabiliTrak traction control are standard across the board, plus the top trim levels have a locking rear differential.
As with many new GM vehicles, OnStar is standard safety equipment on the STS, accompanied by more conventional systems like air bags, rear parking assist, tire pressure monitoring and daytime running lamps. For a luxury vehicle, the V6 does a reasonable job of keeping the environment safe, with an EPA fuel economy rating of 18 mpg around town and 27 on the highway. The V8, of course, sacrifices miles per gallon for performance, with a 15 mpg city/24 mpg highway rating.
Each model has its own selection of trim levels with features that can vary widely. The 3.6-liter has the base model, Luxury trim and Premium trim with all the high-tech goodies standard. The 4.6-liter comes in Luxury and Performance trims with amenities to match.
Remote vehicle start power passenger seat and rear parking assist are standard across the board. The Luxury trim adds Bluetooth, an entertainment system, lumbar support for both front seat passengers, a heated driver's seat. A sunroof is optional. The V6 Premium adds sporty exterior touches such as chrome wheels, xenon HID headlights and a rear spoiler.
The V8 adds heated power mirrors, performance tires, and on the Performance trim, an active suspension system for advanced handling.