Cadillac's Charm

The third time is a charm, as the saying goes.

For General Motors Corp.'s Cadillac Div., it's definitely true. The '05 STS midsize sedan, which replaces the Seville, is the third all-new vehicle based on GM's luxury rear-wheel-drive/all-wheel-drive Sigma platform.

The CTS entry-luxury sedan was Sigma's debut and has been a huge sales hit. The SRX cross/utility vehicle's public reception has not been as impressive, but it arguably has been the best total-vehicle execution of the new-generation Cadillacs.

But now it's time to move aside for the flagship STS sedan, which certainly is the finest vehicle in Cadillac's increasingly impressive lineup.

During an afternoon test-drive near GM's Milford, MI, Proving Grounds, the STS performs flawlessly. It curls through the forest, around marl pits and ponds, and conquers the eastern edge of Michigan's Irish Hills.

The steering is sharpshooter precise. If there is a weakness, it might require a tad too much effort, but it's far from causing the driver to break a sweat.

The STS clenches the asphalt. It's perfectly balanced and devoid of sudden shifts during turns. Sitting on an independent front suspension and multi-link independent rear, STS' ride is taut — you feel you are dictating the road's direction, rather than the opposite.

The ride and handling definitely are the STS' strongest attributes. But what is under the hood isn't shabby either. Take your pick of engines: the 255-hp 3.6L V-6 VVT in the rear-drive configuration, or the 320-hp Northstar 4.6L V-8 in rear- or all-wheel drive. The V-6 is impressive for its broad power availability — ready and able for a wide variety of circumstances. It has legs, considering the STS' hefty 3,897-lb. (1,767-kg) curb weight. (The car tops 4,200 lbs. [1,905 kg] with the V-8 and AWD.)

The graceful Northstar V-8 offers a 20-hp boost from the old Seville. Both engines incorporate variable valve timing and are mated to 5-speed automatic transmissions equipped with the manual-automatic Driver Shift Control. The “manumatic” provides a kick-in-the-pants to the typical sedate sedan. But a 3-pedal version would add a dash of sportiness and excitement.

The STS overcomes the biggest hangup in Cadillac's comeback: subpar interior designs. The cockpit feels like the showroom of a trendy furniture store with its fine mix of wood, Tuscany leather, aluminum and Monaco woven fabric. It's fashion-forward. It's well-crafted. It's plush.

The integrated 6-disc CD/DVD changer with DVD audio, CD and MP3 capability is heard through the 15-speaker Bose personalized 5.1 Surround Sound system. It's the best stereo I've heard — in a car or a house.

The cabin's biggest shortcoming is the rear seat: legroom (38.3 ins./97.2 cm) seems tight. The STS' overall length (196.3 ins./498.6 cm) and width (72.6 ins./184.4 cm) are shorter and narrower, respectively, than Seville.

Another lesser interior deficiency is the upper third of the interior door panels. The material is too rigid and lacks richness.

The exterior styling is softened compared with the diamond-edge designs wrapped around the other Cadillacs (excluding DeVille). But ultimately the STS looks like a super-sized version of the CTS. In fact, as the bus carrying journalists pulled into the parking lot filled with STS sedans for the test drive, several writers wondered aloud why there were CTS models on hand. Cadillac's ice-sculpture styling has been key to its revival, but the design needs to be evolving faster if the auto maker wants to slide by its competition.

2005 Cadillac STS (AWD)

Vehicle type: Front-engine, rear- or all-wheel drive, 5-passenger 4-door sedan

Engine: 4.6L (4,565 cc) DOHC V-8, aluminum block/aluminum heads

Power (SAE net): 320 hp @ 6,400 rpm

Torque: 315 lb.-ft. (459 Nm) @ 4,400 rpm

Compression ratio: 10.5:1

Bore × stroke (mm): 93 × 84

Transmission: 5-speed automatic

Wheelbase: 116.4 ins. (296 cm)

Overall length: 196.3 ins. (499 cm)

Overall width: 72.6 ins. (184 cm)

Overall height: 57.6 ins. (146 cm)

Curb weight: 4,230 lbs. (1,919 kg)

Market competition: Audi A6, BMW 5-Series, Jaguar XJ, Lexus LS 430, Mercedes E-Class