2008 Cadillac STS Road Tests

The STS has been given a substantial facelift for 2008. It's the most significant change in appearance since the STS was introduced as an all-new model for 2005.

For 2008, a new V6 engine comes standard, a 3.6-liter direct-injection V6 developing 302 horsepower. The six-speed automatic transmission introduced on V8 models last year now comes with the V6 as well. Also available is one of GM's most sophisticated V8 engines, boasting the latest in computerized management and variable valve timing. The result is smooth, efficient power. For even more potent grand touring, the super-performance STS-V adds supercharged velocity.

New safety technologies for 2008 include Cadillac's latest Lane Departure Warning and Blind Zone Alert systems, plus a more sophisticated StabiliTrak electronic stability control system that uses steering as well as brake and throttle control to avoid dangerous skids.

The interior of the STS is superb, with comfortable but supportive seats that are infinitely adjustable, ample storage space, and superior sound systems. State-of-the-art occupant safety comes standard as well. Entertainment systems include 15-speaker surround-sound.

The STS is unmistakably a Cadillac, but it's also a four-door performance sedan for people who like to drive. The STS offers a choice of suspensions, from the standard setup designed for smooth, comfortable commuting to an active performance suspension that instantly adjusts to any driving situation, whether cruising through a sea of potholes or accelerating around a sweeping turn. Rear-wheel drive provides the balance and control that serious enthusiasts demand. All-wheel drive is also available, for handling stability in inclement weather.

All-wheel drive is available for the V6 ($1900) and base V8 ($1550), but not the STS-V.

Standard features include leather upholstery, aluminum interior trim, dual-zone automatic climate control, Bose AM/FM/CD stereo, interior auto-dimming rearview mirror, and the usual lineup of power creature comforts and driver aids. OnStar telematics (with one year's service), StabiliTrak electronic stability control, automatic high-beam control (Intellibeam) for the headlights, and rear park assist are also standard.

The popular V6 Luxury Package ($3,540) adds two-driver memory for seats, mirrors, climate and radio controls; Rainsense wipers; six-disc in-dash CD-changer; Eucalyptus wood trim on the instrument panel, steering wheel, console and center stack; heated and ventilated front seats with four-way power lumbar; heated rear seats; heated steering wheel; tire pressure monitor, universal home remote; and a cargo net. The V6 Luxury Performance Package ($5,845) includes all of the above, plus a limited slip rear differential, Premium ZF steering gear, performance cooling package, rear spoiler, Brembo performance brakes, and P235/50R18 front tires and P255/45R18 rear tires on 18-inch polished aluminum wheels. The new Luxury Level Two Package ($705) adds Xenon HID Intellibeam headlamps with washers, a premium sound system, and navigation to V6 models with the Luxury Package.

Much of the content of the V6 Luxury Package is standard on the V8 model. The V8 Luxury Package ($4,200) adds Bose 5.1 surround sound, Xenon HID Intellibeam headlamps with washers, and heated and ventilated front seats. The V8 Luxury Performance Package ($8,190) includes all Luxury Package features plus Premium ZF steering gear, performance cooling, Magnetic Ride Control, rear spoiler, Brembo performance brakes, P235/50R18 front tires, P255/45R18 rear tires, and 18-inch polished aluminum wheels.

A new Performance Handling Package ($1,600) is available for the rear-drive V6 and both rear and all-wheel-drive V8s. It bundles StabiliTrak with the high-performance Brembo brakes and chrome-plated wheels fitted with new P255/45R18 Michelin Pilot Sport summer-only tires. On AWD V8s only, StabiliTrak includes active steering.

Standalone options for V6 and V8 models include the Bose 5.1 surround-sound stereo ($2645), premium Tuscany leather seats ($1295), a power glass sunroof ($1200) and the Brembo brakes ($395). A heads-up display (HUD) is now available on all models ($600), as is an engine block heater ($100). Some paint colors also cost extra ($995). Wood trim ($250) is available for the V6.

A new Platinum Edition features special paint, trim, wheels, and upholstery.

STS-V comes with a higher level of standard equipment, including EZ Key with remote start, XM Satellite Radio, rear AV jacks, rear climate system controls, rear obstacle detection, the Lane Departure Warning System, hand-wrapped leather seats with suede inserts, and olive ash burl wood and aluminum interior accents. Special paint and the engine block heater are the only options; the sunroof can be deleted for credit.

Safety features that come standard on all models include dual two-stage frontal airbags, front seat-mounted side airbags, and front-and-rear side curtain airbags. Four-wheel anti-lock brakes are standard, along with StabiliTrak electronic stability control. Tire-pressure monitors are standard on V8s and available as part of the Luxury package on V6s. OnStar comes standard; its operators send out the rescue squad if your airbag goes off and you don't respond to calls.

Lane Departure Warning is an optional system that uses a camera located between the inside rearview mirror and the windshield to detect lane markings on the road and alert drivers when they inadvertently stray from the lane. Side Blind Zone Alert is an optional system that uses radar sensors behind the rear fascia that signal an audible and visual alert if objects are detected where it might be difficult for the driver to see them. Adaptive cruise control with head-up display ($1695) is offered only on the V8, and enhanced StabiliTrak with active steering ($995) is available only on V8s with AWD.

Its distinctive profile hasn't changed; in fact, most of the outer skin of the STS is carried over. Its crisp lines draw an almost box-like silhouette that somehow still looks aerodynamic. Perhaps it's the gently curved A-pillar and C-pillar that tend a bit more toward art than science. Sharply contoured lower rocker panels tracking rearward from the front fascia's bottom edge pull the body down, adding a stylistic ground-effects look. It's all very consistent with Cadillac's Art and Science design motif.

Up front, however, the 2008 STS has abandoned any semblance of modern, European-style subtlety in favor of a boldly traditional eggcrate grin. Cadillac says the new dual-textured, multi-faceted grille was inspired by the Sixteen concept car, but to us it looks like a re-run from 1969, an impression compounded by Cadillac's now-trademark vertically stacked headlamps. You can like it or leave it, but Cadillac is clearly embracing it, because you'll find it on the 2008 Escalade and CTS, too.

In a similar vein, chromed air extractor vents now mark the previously clean flanks. More subtle chrome accents have been added to the door handles and rocker flares. New 18x8-inch, 14-spoke polished aluminum wheels are available.

The backside is vaguely reminiscent of the old Eldorado coupe, with vertical taillights bracketing a tall, squared-off boot. Recessed in the boot's rear vertical is a trapezoidal inset, long enough for European-spec license plates, housing large backup lights at the left and right extremes. The last things you see as an STS flashes by are new three-inch polished aluminum exhaust tips, exiting below and at each end of the rear bumper.

You can be forgiven for mistaking the STS for the smaller, and similarly redesigned CTS. The two 2008 models are almost indistinguishable to the casual observer, even when parked side by side. Both cars present only minimally different iterations of the same sharp angles and flat planes. Both now wear the same vintage dollar grin grille. The STS and CTS share platforms, but the wheelbase of the STS is three and a half inches longer than that of the CTS, and its body is nearly five inches longer overall.

The Platinum Edition features 18-inch chrome-finish wheels, an even brighter chrome-finish grille; bright chrome inserts on the exterior door handles, and special Glacier Gold paint.

The super-performance STS-V avoids the retro look up front with polished stainless wire-mesh grilles above and below the front bumper, and a not particularly subtle power bulge in its engine hood. Its deeper front air dam incorporates brake scoops below the fog lights. STS-V gets the new fender vents, but they seem more in line with the performance model's extroverted character. Its 10-spoke wheels are unique; its rear spoiler more obvious. And in case you miss all that, it's distinguished by V-Series badging and Supercharged lettering on the front doors.

The seats in all models are refreshingly supportive, for a Cadillac, without being overly firm. Arm rests and head restraints are a degree or two softer than the cushions and side bolsters, boosting the comfort factor a couple notches. All essential controls are within easy reach, although there could be more clearance between the lower door panels and seat bottom to access the front seat adjusters. For this reason, we were especially grateful for the seat memory feature, which often saved us from having to reach down there. The interior is noticeably roomier than that of the marginally smaller CTS.

Instruments are easily scanned, white-on-black round analog gauges, with a large nested tachometer and speedometer between the smaller fuel and engine temperature gauges. The speedometer changes between English and metric electronically, so there's only one set of numbers around its circumference.

Cruise control and running lights are managed via a stalk on the left side of the steering column, windshield wipers and washers with a stalk on the right. Buttons in the steering wheel spokes provide redundant controls for audio and driver information functions. The steering wheel hub has been re-shaped for 2008; it now looks more substantial, even a bit futuristic, but not all that different from before. The available head-up display projects speed and other key information onto the windshield, so that the driver does not need to look down at the gauges.

The available Bose 5.1 stereo incorporates one of the industry's first OEM-installed surround-sound systems. Fifteen Bose speakers do the job, plus an integrated six-disc CD/DVD changer that plays DVD-A, CD, and MP3 formats. The setup also includes an eight-inch VGA-quality touch screen and advanced navigation, Bluetooth phone capability, and OnStar with advanced voice recognition. A word of caution, however: the top-level stereo system, although delivering superb surround-sound, is multi-tasked with a navigation system that, in combination, demands an extensive study of the owner's manual to operate with any degree of alacrity and confidence.

The 2008 OnStar system features a fully integrated GPS navigation setup called Turn-by-Turn Navigation. Turn-by-Turn allows drivers to talk to a live advisor, who can download complete step-by-step directions to the vehicle through the OnStar system. These audio directions then automatically play through the vehicle's stereo as needed (after the OnStar operator hangs up), triggered by the system's GPS capabilities. This enables drivers to be led to their destination while keeping their hands on the wheel and eyes on the road.

Storage cubbies include map pockets in all four doors. The front center console is deep and wide and pre-wired for cellular and Bluetooth (to wirelessly tie a cell phone into the car's audio system, allowing hand-free operation). The glove box, though, is barely sufficient to hold the navigation DVD case and owner's manual. Two cup holders are provided front and rear. The trunk is fully lined, with articulated, gas-pressurized struts.

Fit and finish are top grade, with notably tight trim tolerances. Careful attention was paid to reducing noise, vibration and harshness, with remarkable and commendable success. Specially laminated windshield and front door glass, wind tunnel-tuned outside mirrors and high-density/low-mass sound-deadening padding make this a quiet car even by Cadillac standards.

The Platinum Edition features hand-cut and hand-sewn leather on the instrument panel, door trim and center console areas. The steering wheel is heated. The seats are fully covered with a semi-aniline leather called Tuscany. Wood trim is an olive ash burl stained a saddle shade. Chrome accents highlight the instrument panel and doors. Even the floor mats are upgraded, and there are Platinum badges on the door sills. Only two interior colors are offered: Cocoa over Cashmere or all-Ebony.

New for 2008, the V6 delivers 302 horsepower at 6300 rpm (47 more horsepower than 2007) and 272 pound-feet of torque at 5200 rpm (an upgrade of 20 pound-feet over the 2007 V6). At the same time, GM expects the new V6 to deliver improved fuel efficiency, while its direct injection technology enables a 25 percent reduction in cold-start hydrocarbon emissions. (With direct injection, fuel is sprayed directly into the cylinder, where it mixes with air, rather than in the intake port. As the fuel vaporizes in the cylinder, the air and fuel mixture is cooled. This enables the use of a higher, 11.3:1 compression ratio for better thermodynamic efficiency. The 3.6-liter V6 also features the U.S. industry's first isolated fuel-injector system, which helps reduce engine noise.)

The six-speed automatic (Hydra-Matic 6L50) that comes on all models features a generous 13.88:1 maximum overall ratio for rapid launching off the line (13.11 with AWD), while also providing two tall overdrive ratios that decrease engine rpm and reduce noise levels while cruising at highway speeds.

The V8 generates 320 horsepower at 6400 rpm, and 315 pound-feet of torque at 4400 rpm. Both the 3.6-liter V6 and 4.6-liter V8 use electronic throttle control, commonly called drive-by-wire, to match the engine's performance to a variety of driver demands, from sedate highway cruising to rambunctious back-road motoring.

The STS-V's 4.4-liter supercharged V8 pumps out 469 horsepower, making it the most powerful engine in Cadillac history. It makes 439 pound-feet of torque, with 90 percent of it available in a wide sweep from 2200 to 6000 rpm. This enormous thrust is delivered smoothly through the six-speed automatic transmission. However, the heavy-duty upgrades found in virtually every dynamic element of V-model car, including harder-riding lower-profile tires, make the STS-V only suitable for those willing to sacrifice some comfort in return for jetting from 0 to 60 mph in less than 5 seconds. There's also the STS-V's $1700 gas guzzler tax to consider.

For most people, then, the sporty setup will be the STS V8 with the optional performance handling package. Nudge the shift lever over to the right, into the manu-matic gate, and the selected gear will hold all the way up to redline. Alternating between the accelerator and brake pedal allows frolicking at extremes heretofore beyond the reach of sedans wearing the wreath and crest. Cadillac's suspension engineers have demonstrated they understand the difference between stiff and firm. Thankfully, all the sound filtering and deadening doesn't keep the V8's throaty exhaust note out of the cabin.

The all-wheel-drive system is a hard package to top, however, complemented by Magnetic Ride Control and the latest generation StabiliTrak, though this adds some weight. Still, body lean in even the tightest switchbacks is almost non-existent, and mild whoop-de-doos barely give occupants' stomach a flip. Biasing 60 percent of the power to the rear wheels gives the all-wheel-drive STS the sporty dynamics of rear-wheel drive while sending enough power to the front wheels to pull the car through and out of corners with sureness and confidence.

Either way, the electronic steering is a delight, its only shortcoming a slight softness on center. The STS tracks well through corners; and turn-in is crisp, especially with the 18-inch, low-profile tires.

Active steering, available exclusively on V8 models with AWD, is integrated into the StabiliTrak stability control electronics. In addition to controlling brakes and reducing engine power, StabiliTrak with active steering can turn the front wheels to reduce skidding when rear wheels lose traction. The system includes a new steering motor assembly combined with computer-driven electronic controls that measure wheel slippage at all four wheels independently during acceleration, braking and adverse road conditions.

Brakes on the STS are up to the car's potential, with a firm pedal and a feel that's more linear than not. All of the various Performance packages include four-piston Brembo calipers, with 13.9-inch rotors up front and monster 14.3's in the rear. All four rotors are vented.

The Lane Departure Warning system engages above 35 mph. A green light indicates that the system is turned on and working. Should the driver cross a detected lane marking without signaling, the light flashes amber while an alarm beeps three times. The system is designed to alert drivers so they can take appropriate action to move the vehicle back into their own lane. To avoid nuisance alerts, the system is designed to not provide an alert if the turn signal is on or if the driver makes a sharp maneuver. Thankfully, the driver can also switch it off, in which case the light goes out entirely.

The Side Blind Zone Alert system uses radar to sweep an 11-foot zone on either side of the vehicle, in other words, about one lane over. The zone starts at each side mirror and reaches back about 16 feet. With the system engaged, an amber symbol lights up in the outside mirror whenever another vehicle enters this blind zone. Cadillac cautions that the system is not designed to detect vehicles outside of the side blind zone that may be rapidly approaching, or pedestrians, bicyclists or animals. It's designed to ignore infrastructure such as fire hydrants or parked cars. In addition, the system displays do not come on while the vehicle is approaching or passing other vehicles.

All three engines represent the latest GM thinking, with double overhead cams, four valves per cylinder and variable-valve timing. Called VVT, this latter system continuously varies valve operation to generate the most power from the least amount of fuel with the lowest emissions possible. Torque is what most of us experience as power in everyday driving; torque is what gets a car moving in the first place, like when accelerating from an intersection. Recognizing that, Cadillac engineers designed the STS engines to generate lots of torque throughout the rev range for responsive performance at all engine speeds.

NewCarTestDrive.com correspondent Tom Lankard reported on the STS, with Greg Brown reporting on the STS-V, and John F. Katz reporting on the styling revisions.