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How Chevrolet Works

Chevrolet Impala LTZ and Chevrolet Monte Carlo SS

The Impala and Monte Carlo underwent an extensive 2006 makeover. The update was particularly crucial for the top-selling Impala. GM literally couldn't afford to get it wrong. And at first glance, it didn't.

Though the old W-body persisted, Chevy gave the sedans and coupes clean new styling, modernized interiors, and a much-revised suspension that aimed to up driving fun without compromising comfort. Parallel lineups listed base LS and LS 3.5 models with a 211-bhp 3.5 V-6, plus LT 3.9 and luxury LTZ versions with a 242-bhp 3.9-liter V-6.

But the real news was the return of V-8 power for the SS Impala and Monte Carlo. This was the 5.3-liter overhead-valve unit already familiar in midsize Chevy trucks, enhanced by GM's new Active Fuel Management system, once known as Displacement on Demand.

Recalling Cadillac's "V-8-6-4" engine of 25 years before, AFM was designed to save fuel under light throttle loads by automatically shutting down cylinders -- four in this case.

But unlike the hapless Caddy engine, the AFM 5.3 was glitch-free and virtually seamless in operation, reflecting huge advances in electronic engine controls since the early 1980s.

Though AFM couldn't make the V-8 yield minicar fuel thrift -- an Impala SS tested by Consumer Guide® logged 20.3 mpg in mostly highway driving versus the EPA estimated 18/28 city/highway -- it was a selling point at a time when record gas prices had people looking for the best mileage they could get.

Just as timely, GM tuned the 3.5-liter V-6 to run on E85, a mix of 15 percent gasoline and 85 percent ethanol. E85 not only tended to be cheaper than regular gas, it also burned cleaner, a fact that appealed to the environmentally conscious.

And because ethanol is made from corn and other renewable sources, it promised to reduce the country's dependence on foreign oil, another selling point in an age of increasingly tight oil supplies.

E85 aside, however, there was frankly little to get ­excited about in the latest Impala and Monte Carlo. Consumer Guide® judged Impala "affordable, relatively roomy, and has competent road manners.

Powertrains are improved for 2006, and curtain side airbags are available for the first time. But this sedan still feels dated compared to midsize-car-class pacesetters, the Honda Accord and Toyota Camry. In the same vein, Monte Carlo is a throwback to the era of the midsize domestic coupe."

Harsh words, but perhaps mitigated by the likelihood of clean-sheet replacements with rear-wheel drive by 2010, perhaps sooner.

Critics can argue that Chevrolet and the GM still have much catching up to do, and the sooner, the better for GM workers, stakeholders, and customers. But Rome wasn't rebuilt in a day, and GM is making progress.

At Chevrolet it takes the form of needed new full-size SUVs and pickups for 2007, refinements to popular newer fare like the Equinox "crossover" SUV, and weeding out peripheral products, however attention-getting, like SSR (born 2003, terminated after 2006).

We should also note that Chevrolet was again "USA-1" in 2005, besting a faltering Ford in total calendar-year car and truck sales for the first time in two decades. That's got to count for something.

For more on Chevrolet cars, old and new, see:

  • Chevrolet New Car Reviews and Prices
  • Chevrolet Used Car Reviews and Prices