2005 CADILLAC STS: SOPHISTICATED PERFORMANCE AND LUXURY

The 2005 Cadillac STS is the luxury nameplate’s all-new luxury performance sedan. It has been designed, engineered and executed to deliver precision craftsmanship, outstanding performance, and sophisticated luxury in a distinctly American package.

Based on General Motors’ new rear-wheel-drive Sigma architecture, which also is the foundation for Cadillac’s entry-luxury CTS sedan, CTS V-series high-performance sedan, and SRX luxury performance utility – the STS is designed to compete head-on with world-renowned prestige sedans in markets around the globe.

“Our long-term goal for Cadillac is to become the Standard of the World once again,” said Mark LaNeve, general manager for Cadillac. “In order to succeed globally, we have to build vehicles that have outstanding performance, exceptional quality and reliability, and meet the demands of the most discerning car buyers. “The STS represents the latest step in that direction.”

From its Cadillac-signature bold exterior styling to its outstanding power and road capabilities, the STS is the product of unwavering attention to detail. More than 1,000 criteria points have been strictly adhered to throughout development of the vehicle. The result is outstanding fit and finish, overall harmony, refined performance and purposeful innovation.

“We feel very comfortable calling this a finely crafted car, but we also realize that’s the price of entry into this category,” said Jim Taylor, GM vehicle line executive, prestige vehicles. “The STS has simply been engineered to more than hold its own when matched against some of the best prestige luxury sedans in the world.”

While its overall shape brings a faster profile and more rake than its CTS sibling, it’s done so in the context of elegance and grace. Overall, the STS is 196-inches long, 72.6 inches wide and 57.6-inches high, making it the largest sedan offering in the Sigma-based family.

The exterior fit and finish on the STS is taking Cadillac to the next level of refinement and exemplifies the attention to detail seen throughout the vehicle. Body and exterior dimensions are precisely executed. Radii on major body components, such as the hood and decklid, are tight and contribute to its crisp exterior appearance. Doors-into-roof construction and a superplastic-formed aluminum decklid ensure a clean and refined exterior.

All interior gaps also achieve exceptionally close tolerances, enabling a tight, well-crafted appearance throughout. Eucalyptus wood and/or in-mold processed, dent and mar resistant aluminum trim is found on the steering wheel, center console, instrument panel, and door armrests.

Premium materials and fabrics are used throughout the interior. Dual-firmness Tuscany all-leather seats, available as heated and ventilated, are specially tanned for a softer feel. Spray-skinned urethane/natural grained surfaces on the door and instrument panel ensure an inviting, tactile touch, as do the headliner and interior pillars, which are soft backed and covered with a Monaco woven fabric.

In terms of performance, the STS will be available with a 255-horsepower 3.6L V-6 in a rear-drive configuration, or the 320-horsepower Northstar 4.6L V-8 in both rear- and all-wheel-drive configurations. Both engines incorporate variable valve timing (VVT) and are mated to widely acclaimed 5-speed automatic transmissions with Driver Shift Control.

While the STS is true to Cadillac’s performance-oriented roots, a host of chassis refinements ensure that it hits the “sweet-spot” of ride and handling, resulting in a ride that keeps drivers fresh and comfortable without sacrificing the driving experience.

Road impacts and other harsh inputs are effectively absorbed and dissipated through ride-tuned tires, dampers, suspension components and bushings, as well as improved structure in body to chassis interfaces and additional refinements in the engine mounts.

Integrated chassis control technologies include a two-mode Magnetic Ride Control offering performance or touring selections, four-channel StabiliTrak, and an available high-precision ZF steering gear.

Technological appointments on the STS are plentiful, purposeful, and driver oriented. Such applications include an Easy Key system; Smart Remote Start system (not available in Europe or Russia); Adaptive Cruise Control (ACC); Intellibeam; re-configurable, four-color Head-Up Display (HUD); heated and ventilated seats; and heated steering wheel.

Of particular note is an available up-level infotainment system, which includes one of the industry’s first OEM-installed surround sound audio systems. The cabin is immersed with 15 speakers from Bose Corporation. The 5.1 Bose system also has an integrated six-disc CD/DVD changer and is capable of playing a broad array of formats including DVD-A, CD, and MP3. It includes an eight-inch VGA quality touch screen and advanced navigation. In addition, the system has Bluetooth capability, advanced voice recognition, and OnStar.

Like its Sigma-based siblings, the all-new STS will be built at GM’s state-of-the-art Lansing Grand River assembly center in Lansing, Mich., beginning in the summer of 2004.

The STS is expected to arrive in Cadillac showrooms in the fourth quarter of 2004. Beginning in 2005, the STS will be available in Europe, Japan, Russia, Middle East, South Korea, Taiwan and Israel.

POWERTRAIN: STS DELIVERS REFINED POWER, TORQUE

With delivery to showrooms scheduled for the fourth quarter of 2004, the all-new 2005 STS will be Cadillac’s first rear-wheel-drive entry in the luxury performance sedan segment in more than 25 years, and its first-ever all-wheel-drive sedan offering.

The STS will be equipped with two engine offerings, including a 320-horsepower 4.6-liter Northstar V-8 with 315 lb-ft of torque, or 3.6-liter 255-horsepower V-6 with 252 lb-ft of torque (estimated). The STS also will be available with all-wheel-drive (AWD) on vehicles equipped with the Northstar V-8.

The 4.6-liter Northstar is expected to deliver 0 to 60 performance at or less than 6.0 seconds. With the V-6 or AWD V-8, the STS is targeted to achieve 0 to 60 performance in under 7.0 seconds.

The V-6 and V-8 are mated to electronically controlled five-speed automatic transmissions – the Hydra-Matic 5L40-E is mated with the V-6, and the Hydra-Matic 5L50-E is mated with the V-8 and has both rear- and all-wheel-drive applications. The 5L50-E is designed to handle the V8’s torque, with a 25 percent torque capacity increase over that of the 5L40-E.

3.6-liter V-6 VVT engine:
The 60-degree 3.6-liter V-6 is a highly refined, DOHC four-valves-per-cylinder engine with all-aluminum construction. The valve train configuration includes roller finger followers.

The adoption of fully variable valve timing for both intake and exhaust valves provides outstanding flexibility, fuel economy and emissions reduction. The four-cam variable valve timing is a key element in the V-6’s control strategy, which gives the engine a wide-ranging flexibility. For example, 90 percent of the 3.6L V-6’s peak torque is available across a remarkably broad operating range: from 1,600 rpm to 5,800 rpm. In addition, an electronically controlled throttle (ETC) effectively coordinates the driver’s intentions with the actions of the various control components.

Numerous design features were incorporated into the 3.6-liter engine to ensure it is one of the most advanced V-6 offerings in the world. These include:

• A dual-stage variable intake manifold (VIM). The VIM incorporates a switch in the manifold that automatically changes the plenum volume available for resonance tuning of the inlet flow path.
• Micro-hybrid engine control unit (ECU). The V-6’s ECU represents the latest in engine-management hardware, as well as the software that dictates every aspect of engine operation.
• Specially isolated cam covers incorporate an isolated gasket around the cover perimeter and radial lip seals at the tubes through which each spark is inserted.
• Three pressure-actuated piston-cooling oil-jet assemblies in the block each hold a pair of oil squirters that douse the underside of the piston and the surrounding cylinder wall with cooling oil. The benefit is piston temperatures resulting in more engine power.
• Polymer coating on the piston skirts helps the piston to track more smoothly and quietly in the bore.
• A new oil pump design, the product of a highly specialized analysis of pump flow, prevents noise caused by oil aeration.
• A forged steel crankshaft delivers additional stiffness for better noise, vibration and harshness performance; ensures the durability required of high specific output variants; and provides an extra degree of robustness.

Northstar V-8 engine:
The 4.6-liter Northstar V-8 is a 90-degree DOHC four-valve-per-cylinder engine, with an aluminum block and cylinder heads and valve train with roller finger followers. The Northstar is equipped with a host of technologies, including:

• Four-cam continuously variable valve timing (VVT) for improved performance, refinement, economy and emissions.
• Electronic throttle control, providing additional driving refinement. This allows the engine control system to precisely and seamlessly tailor vehicle performance to the driver demands.
• Low restriction intake and exhaust manifolds and cylinder head ports designed to ensure optimum airflow and cylinder-to-cylinder distribution for maximum performance and emissions control.
• Close coupled catalytic converters, mounted directly adjacent to the exhaust manifolds. They reach effective operating temperature more rapidly after engine start.
• New air induction system, redesigned for enhanced capacity and noise attenuation. It features tuned resonators, additional resonators in the clean air duct and use of isolator pads in the clean air duct mounting.
• Powerful engine control module (ECM) and high-speed communication system dedicated to engine control. An extremely powerful, state-of-the-art ECM, with a 16-bit, 24 MHz dual microprocessor, high memory capacity, and a redundant “safety” processor backing up the ETC enables the Northstar engine to provide its advanced capabilities. A transmission control module (TCM) controls the transmission with inputs from the ECM.
• Polymer-coated pistons and cast-iron exhaust manifolds to further reduce noise, vibration and harshness.
• A forged steel crankshaft delivers additional stiffness for better noise, vibration and harshness performance; ensures the durability required of high specific output variants; and provides an extra degree of robustness.

Rear wheel drive:
Rear-wheel-drive STS offerings (V-8 and V-6) offer an available limited slip differential, which mechanically limits wheel spin on all surfaces for improved vehicle performance during handling maneuvers.

Vehicles equipped with the V-6, which are only available in rear-wheel-drive, have a performance-optimized drive ratio of 3.42.

Vehicles equipped with the V-8 engine are available with three final drive ratios configurations; 2.73 for enhanced fuel economy; 3.23 for mid-sport performance; and a 3.42 for optimized performance. Exported vehicles are only equipped with the 3.42 final drive.

All wheel drive:
Vehicles equipped with all wheel drive (V-8-equipped vehicles only) have a final drive ratio of 3.23. The system incorporates a 40/60 rear bias torque split to provide the STS with superior handling performance, acceleration, traction, and control for dry, wet, icy, and snowy road conditions. Its three open differential layout, coupled with four-wheel traction control, balances driving torque distribution to each wheel and minimizes wheel spin to optimize on-road performance.

Electronically controlled transmissions:
The V-8 and V-6 are mated to electronically controlled five-speed automatic transmissions – the Hydra-Matic 5L50-E is mated with the V-8, and the Hydra-Matic 5L40-E with the V-6. Both transmissions incorporate Driver Shift Control (DSC) and Performance Algorithm Liftfoot (PAL) technologies.

Driver Shift Control enables the driver to switch from automatic to a clutchless five-speed high-performance manual transmission. Once the driver moves the gearshift lever into DSC mode, a quick tap is all that is required for smooth, crisp upshifts or downshifts within a selected range.

Performance Algorithm Liftfoot inhibits upshifts while maintaining engine braking following continuous performance driving. The transmission control module (TCM) monitors driver behavior to determine whether or not to enable this feature. For example, if the system detects a drop in vehicle speed prior to entering a turn or a lane change, up to two downshifts can occur to provide the driver with maximum vehicle performance.

INNOVATION: PURPOSEFUL TECHNOLOGY

The all-new 2005 Cadillac STS is equipped with purposeful technologies developed to ensure an outstanding vehicle experience in terms of luxury, comfort, convenience and safety.

The technological backbone of the STS comes in the form of the GM LAN Serial Data Electrical Architecture – a high- and low-speed data network that connects system modules and ensures that information is properly communicated and shared between them.

In all, the STS is equipped with up to 27 modules, located throughout the vehicle, depending upon options selected. Each module sends and receives information sent via the GM LAN.

This electrical architecture enables the host of purposeful technologies offered on the STS.

Keyless Access with push button start:
Keyless Access enables passive vehicle and trunk entry and push-button ignition via a personalized, keyless fob. With the key fob in a pocket or purse, a person can approach a locked vehicle, pull the door handle and open the door. The same concept applies when opening the trunk. As a result, the need to pull keys out – or even the fob – to activate the door and trunk functions has been eliminated. The system uses passive and active antennas to detect the vehicle fob and its proximity to the vehicle.

Keyless Access works in tandem with the vehicle security system, enabling the STS to be started with a momentary push of a button located on the instrument panel. To start the vehicle, the fob must be inside the vehicle, and the brake pedal depressed.

Smart Remote Start system:
The Smart Remote Start system, which operates from as far as 200 feet, not only starts the vehicle via fob activation but also automatically adjusts a variety of personalization settings in the process.

When activated via the Smart Remote Start system, the STS – based on temperature inputs – begins to acclimate the occupant environment before the driver gets to the vehicle. Once remote start is initiated, the vehicle:

• Adjusts climate control to previously set cabin temperature.
• Begins seat heat or ventilation (based on feedback from outside temperature settings).
• Activates front and rear window defroster if climate conditions require it.

This extension of functionality is made possible by the electrical architecture on the STS, which allows various systems in the vehicle to work in concert.

Adaptive Cruise Control:
The STS can be equipped with Adaptive Cruise Control (ACC), which greatly increases the value and comfort of cruise control, especially in congested traffic situations.

The system uses a radar sensor mounted at the front of the STS that is located behind the grille-mounted wreath & crest to detect objects in its path. If the lane ahead is clear, the system will maintain the set speed. When slower traffic is detected, the system will automatically adjust to a safe distance (which is selected by the driver) by using throttle control and limited braking.

The ACC system used on the STS also incorporates two new features: grade braking and audible alert. With grade braking, the transmission will automatically downshift to maintain selected vehicle speed and distance, preventing overheating of brakes.

The audible alert function operates when ACC is active, notifying the driver when he/she is too close to a preceding vehicle. All adaptive cruise displays are shown through the four-color, reconfigurable head-up display (HUD).

High-performance forward lighting system;
The STS is equipped with large 70-millimeter projector beam headlamps for outstanding forward- and spread-light performance. Two projector beams are stacked vertically in each headlamp housing; the upper projectors provide low-beam illumination, and all four projectors are illuminated for high-beam performance.

The tungsten halogen lighting provides an outstanding “punch” – or down the road – lighting as well as excellent spread light. When equipped with an optional high-intensity discharge (HID) xenon lighting system, the 70-millimeter projectors provide even greater forward and spread light. The HID application includes headlamp washers, which are integrated flush to surface on the adjacent front fascia.

On vehicles sold outside North America, the STS will only be equipped with the HID lighting system as well as a dynamic headlamp leveling system – a feature where the lens automatically aligns itself to the vertical height of the road based on vehicle pitch.

Intellibeam:
Intellibeam automatically switches headlamps from high- to low-beam and back again when oncoming headlamps or forward lighting elements are sensed. The system makes nighttime driving safer by providing the maximum amount of light possible for any driving scenario.

The system uses a state-of-the-art complimentary metal-oxide semiconductor (CMOS) light sensor. Located on the back of the rearview mirror, the CMOS contains a miniature camera, light sensors and microprocessor that sense oncoming light. When it detects an approaching vehicle’s headlights or preceding vehicle’s taillamps, the system turns off the high beams gradually before it distracts other drivers. The system also detects and effectively ignores ambient light coming from streetlights, sign reflections, buildings and other sources.

In situations where light from an approaching vehicle is more immediate, such as when cresting a hill, the Intellibeam system reacts instantaneously, automatically switching to low-beam output of light.

Reconfigurable four-color head-up display:
The STS will incorporate a day/night head-up display (HUD) application that is four-color and reconfigurable.

The HUD will incorporate an infotainment data display, tap gear display, shift indicator display and ACC display as well as turn-by-turn directional navigation and audio band, frequency, and pre-set information – all based on driver preference. It is also configurable to five languages: English, French, Spanish, German, and Italian.

A switch located on the instrument panel allows the driver to turn the system off or on.

Bose Studio Surround Sound audio system:
One of the industry’s first OEM-installed surround sound audio system – developed by Bose – incorporates 15 speakers and provides concert quality sound to both front occupants and passengers in the rear compartment.

The optional 300-watt system incorporates the following elements for unmatched 5.1 channel surround sound quality and performance:

• Four 50-millimeter mid-high range speakers integrated with two in each of the driver and front passenger seats.
• Two 2.5-inch full-range outboard speakers positioned in the instrument panel.
• Four 3.5-inch full-range speakers located in the instrument panel, rear console, and rear shelf.
• Two 9-inch powered Neodynium (Nd) woofer assemblies located in the driver and front passenger doors.
• Two 5.25-inch full-range speakers positioned in the rear doors.
• A 12-inch powered Nd sub woofer located in the center position of the rear shelf.
• A surround amplifier positioned on the rear shelf.
• A VNC microphone positioned to the driver’s lower right.

The system incorporates proprietary processing technology from Bose, which makes two-channel audio information very rich and spacious. Base radio system features on the STS include dedicated presets for two drivers (up to 36 each) for AM, FM and XM Satellite Radio reception as well as the ability to seek across bands. The base system also includes expanded information display for XM, FM-RDS and CD MP3.

Six-disc in-dash DVD/CD changer:
An optional factory-installed, in-dash six-disc DVD changer supports a variety of media formats and includes 5.1 channel surround sound. The system also incorporates dual media slots – one for entertainment and the other for DVD-based navigation – greatly reducing time changing media and ensuring full-time navigation capability.

Media formats supported by the DVD system include DVD audio, DVD video, CD audio and MP3. Media types supported are CD/DVD ROM and CD/DVD-R. DVD video can only be activated when the vehicle is in “park”.

Large infotainment display;
When equipped with an uplevel infotainment package, the STS has an industry-largest 8-inch diagonal high-resolution full VGA infotainment display head with full touch screen and four-position tilt function.

The display head – which is positioned high in the center stack and is flush with the surface of the instrument panel – provides unmatched clarity enabled by 800-by-480 pixel resolution. A large viewable area (approximately 104-by-174 mm) is 20 percent larger than most current offerings.

The four position tilt-screen incorporates memory recall and offers 5-, 10-, and 15-degrees of tilt, enabling the driver to select the best viewing angle based on environmental conditions.

Enhanced DVD-based navigation system:
The DVD-based navigation system available on the STS conducts route calculation 30 percent faster than current systems, displays freeway exit information (gas, restaurants, services) via expandable icons, and covers all roads and streets in the U.S. and Canada (nearly seven million miles) on a single map DVD. The system allows route planning to items stored in memory via voice commands and/or voice tags.

A broad range of location search options is available, making location selection more user friendly.

Cellular phone compatibility:
The STS has cellular telephone accommodation for the factory-installed OnStar system and portable Bluetooth capable phones through the uplevel infotainment system, which enable hands-free operation, screen and voice dialing of phone numbers.

Enhanced voice recognition:
An enhanced voice-recognition system on the STS offers continuous speech capability, multiple language support (English, French, Spanish, German, and Italian) and more than 150 voice commands, including those for infotainment and HVAC, among other functions.

CRAFTSMANSHIP: DETAIL FROM STRUCTURE TO SHEET METAL

From the inner structure to the exterior sheet metal, the all-new 2005 Cadillac STS has been meticulously crafted to ensure delivery of the attributes expected of a luxury performance sedan.

The STS features a body frame integral (BFI) structure, based on the premium Sigma rear-wheel-drive architecture. With a BFI structure, the upper body structure and sub-frames are engineered as a single unit, enabling a mass efficient, yet stiff, body structure. BFI structures bring an ideal foundation for achieving sports sedan performance as well as achieving broader styling objectives.

As a result of a number of structural enhancements, the beaming frequency on the all-new Cadillac STS is approximately 25 hertz (hz), a stiffness that is highly competitive in its class. In addition, a significant overall torsional stiffness improvement of 13 percent was achieved when compared to the CTS.

The STS is equipped with a host of refinements to ensure a quiet ride and interior environment and impressive wind noise performance.

Laminated front of dash:
The STS joins the CTS and SRX as the first vehicles in GM to be outfitted with a laminated front-of-dash panel – a key enabler to reducing the transfer of engine compartment noise into the cabin. Also called “quiet steel,” the application was first used on the 2003 CTS and is found on all Sigma architecture-based vehicles.

The front-of-dash panel consists of two thin pieces of steel held together by composite adhesive. A sophisticated bonding process ensures the steel will not resonate noise, and damps noise transfer significantly when compared to conventional applications.

Front-of-dash mat:
A front-of-dash mat constructed of a 28-millimeter thick thermal plastic olefin (TPO) cast foam material effectively reduces powertrain noise transfer into the cabin. The mat, essentially a noise-damping blanket on the engine side of the dash panel, is applied with a glove-like fit and closes out all cavities in the panel.

Enhanced body structure impedance at chassis attachments:
All chassis-to-body structure interfaces (i.e., suspension brackets or cradle attachments) on the STS have been redesigned to improve stiffness and structure, thus attenuating low-frequency noise into the cabin. The result is excellent isolation from all such interfaces.

Each of the interfaces has been essentially “tuned” through shape or material thickness (primarily steel) to ensure a robust, stiff structure that effectively minimizes vibrations and related transfer of noise from road irregularities, engine, prop shaft, and other inputs.

Reinforced tunnel:
In order to add greater reinforcement to the center tunnel of the STS, which serves as the “backbone” of the vehicle, a tubular structured U-shaped “strap” was added for tension and compression, again further improving the vehicle’s overall stiffness. It also helps reduce vibration to the floor pan and rear seats.

A constraint layer also is implemented into the tunnel structure – inner and outer steel structures are mated together in a sandwich form. As a result, the two pieces of steel dampen each other, reducing the transfer of noise and vibration into the cockpit.

Constraint layer on shock towers:
To attenuate noise transfer from the shock towers into the passenger compartment, all shock towers are applied with a constraint layer. The layer, two pieces of metal that sandwich a rubber viscous material, makes up the structure of each shock tower. This application significantly reduces the noise level in the passenger compartment.

Constraint layered wheelhouses:
Both rear wheelhouses on the STS are constructed of sandwiched steel structures that mate together as inner and outer structures. As a result, the sandwiched steel pieces dampen each other, greatly reducing the resonation of noise into the rear passenger compartment.

Front tunnel barrier:
A front tunnel barrier is applied under the carpet on the STS to ensure superior isolation from driveline acoustics. The barrier, which runs from the dash panel rearward on either side of the tunnel where it meets the floor, is constructed of a lightweight composite with outstanding noise damping characteristics.

Acoustic windshield and laminated side glass:
An acoustic laminated windshield on the STS is a key enabler to the vehicle’s outstanding wind noise performance. While the windshield itself is thinner than traditional applications (4.8mm vs. 5.4mm) to reduce mass, it still delivers the acoustic performance of thicker glass because of a four-layer construction. Two layers of glass sandwich a safety laminate and an acoustical-grade vinyl sheet laminate, enabling a marked reduction in wind noise.

Similarly, the laminated front side glass provides significant improvement in wind and external noise performance.

Sound damping in cabin:
Lightweight damping material is applied throughout the vehicle cabin and addresses the high- and mid-range frequencies often managed by heavier deadening materials. The material, a foil/rubber acoustical damping compound that is adhesively applied to the inner sheet metal, is a first-time Sigma architecture application.

Trunk acoustics:
Low weight, high-absorption trunk acoustics effectively damp noise and vibration. The trunk acoustics are constructed of a composite material that delivers damping performance of more traditional applications with a mass savings of up to 50 percent.

Structure-less windshield wipers:
Lower profile, structure-less windshield wipers deliver a wind noise reduction when compared with conventional applications.

Also called “flat blades,” the wipers are absent of an arm structure, a common source of noise when wind travels through and around it. It is replaced by a flexible airfoil surface that runs along the top of the blade. The airfoil is “tuned” to the shape of the windshield, ensuring a lower profile and superior contact with the windshield at all positions.

Doors into roof construction:
The doors-into-roof construction on the STS eliminates the need for molding along the top of side window glass and ensures consistent surfaces around the elements. This door execution, inspired by high-performance aircraft, enables extremely tight gap tolerances, and plays a primary role in the integrated, clean and sleek appearance of the STS.

The construction enables “on surface” appearance of the door glass as well as a thin seal appearance around the entire periphery of the door glass opening. The execution not only provides an aesthetic benefit, but a measurable improvement in wind noise as well.

Triple door seals:
The doors-into-roof construction on the STS enables a triple seal architecture around all four doors, a key enabler to reducing vehicle interior noise levels. Three seal sets work together to effectively seal the passenger compartment from wind, water, and other elements.

Superplastic formed decklid:
The aluminum decklid on the STS is a complex shaped form produced using an advanced superplastic forming (SPF) process, an execution that enables a sculpted surface and outstanding dimensional accuracy.

In the superplastic forming process, aluminum is heated to a state of plasticity then formed into a die cavity using air pressure. The final result is a single-piece form, with an integrated pocket for the light emitting diode (LED) CHMSL as well as the backup lamps, that ensures a clean surface throughout the contoured shape of the decklid.

A traditional stamping execution of either steel or aluminum would have resulted in a two-piece execution of the decklid, requiring the use of additional exterior trim.

Fascias:
An integrated, precision-molded front fascia is constructed of thermal plastic olefin (TPO). Its single-piece design eliminates seams, and delivers outstanding dimensional execution to mating surfaces. The fascia incorporates upper and lower grilles and openings for headlamps, park/turn lamps, fog lamps and front side markers.

On vehicles equipped with adaptive cruise control (ACC), the center-mounted badge on the upper grille consists of a composite material that allows pass-through of radar sensing. In addition, HID headlamp washer elements are mounted flush to the fascia’s surface for a smooth, clean appearance.

The rear fascia is similar to the front, and integrates styling lines, exhaust cutouts, rear valance, rear fog lamps (export applications), and cleanly integrates the rear parking assist sensors.

STS DESIGN: SOPHISTICATED AND UNMISTAKABLY CADILLAC

Like its CTS, SRX, and XLR siblings, the all-new 2005 Cadillac STS stands alone as the distinctly bold offering of luxury and style in its competitive set.

However, while the STS carries the design vocabulary, heritage cues and styling characteristics found throughout the Cadillac product portfolio, it does so in a manner that is refined and sophisticated. It is intentionally crafted to meet the discriminating tastes and demands of the segment in which it competes – the most discerning buyers in the automobile marketplace.

The exterior fit and finish on the STS is taking Cadillac to the next level of refinement and exemplifies the attention to detail seen throughout the vehicle. Body and exterior dimensions are precisely executed. Radii on major body components, such as the hood and decklid, are tight and contribute to its crisp exterior appearance. Doors-into-roof construction and a superplastic-formed aluminum decklid ensure a clean and refined exterior.

Overall, the STS is 196-inches long, 72.6 inches wide and 57.6-inches high, making it the largest sedan offering in the Sigma-based family. As a result, the STS delivers exceptional interior spaciousness for front and rear passengers alike. Front legroom, shoulder and head room are 42.6, 58.6, and 38.7-inches respectively; related rear passenger dimensions are 38.3, 54.4, and 37.9-inches. All are near or at the top of the STS’ competitive class.

Distinctive, bold exterior
At first glance, there’s no mistaking the STS as a contemporary Cadillac, with its vertically stacked headlamps and light-emitting diode (LED) tail lamps, signature LED CHMSL, airfoil grille, horizontal spline lines, and dihedral-shaped hood.

While its overall shape brings a faster profile and more rake than its CTS sibling, it’s done so in the context of elegance and grace. Doors-into-roof construction enables more tumblehome, the vehicle sides are sculpted inward, delivering a look of upscale rear-wheel-drive performance with a lower roof line, while maintaining a roomy interior. In addition, a wider tapering sail panel; lower, more sculptured hood; smoother wheel openings; and a tighter wheel-to-body relationship further communicate the agility of the STS, as well as sophistication and substance.

Seven-spoke 17- or available nine-spoke 18-inch wheels lead to larger, higher-performance calipers and rotors, leaving no doubt about the STS’ luxury performance competence. A wire mesh, electro-polished stainless steel lower grille reiterates the statement.

A wheelbase of 116.4-inches and front/rear track of 61.8/62.3-inches, combined with a flush wheel-to-body relationship, ensures well-grounded appeal and presence.

The rocker treatments on the vehicle are specific to the STS, bringing a more sculpted shape to the vehicle’s lower line for more presence and refinement. A single-piece fascia design, which eliminates seams for a clean, uninterrupted appearance, enables excellent fit and finish.

Vertically stacked headlamps, a traditional Cadillac cue, are slightly narrower and lower than what’s seen on the siblings of STS. The headlamps incorporate large, dual 70-millimeter projector lenses encased in an aluminized, single piece bezel.

LED tail lamps are designed with indirect optics, an industry-first application, and incorporate 30 sources of illumination per unit. The use of indirect optics eliminates “pinpoints” of light normally associated with LEDs and enables a very upscale, refined appearance when illuminated.

On the STS, each tail lamp has two vertical arrays consisting of 15 LEDs, and each LED has 20 optical facets. This configuration enables very precise illumination tuning and the design flexibility needed to meet domestic or export requirements.

The LED CHMSL on the STS is only 12-millimeters thick and consists of 78 points of illumination. An ingenious lens design incorporates the use of pillow optics, which again replaces a “pinpoint” appearance normally associated with LEDs with a smooth, refined output of light.

The rear portion of the STS is clean and uninterrupted, due in large part to a one-piece superplastic-formed aluminum decklid with an integrated pocket on the trailing edge for the LED CHMSL. Use of the superplastic forming process enabled integration of rear lighting elements without use of additional appliqués or trim.

The 2005 STS will offer a selection exterior paint colors, five of which are new offerings for STS. The colors are:

• Blue Chip.
• Red Line (new).
• Black Raven.
• Silver Smoke (new).
• Sand Storm (new).
• Moonstone (new).
• Light Platinum.
• Silver Green Metallic (new).

Crafted, inviting interior
The interior of the STS is executed to extremely close and demanding tolerances, enabling a tight, well-crafted appearance throughout. Eucalyptus wood is found on the steering wheel, center console, instrument panel, and door armrests. Other finishes, such as in-mold processed aluminum (dent and mar resistant), are also used.

Premium surfaces are found throughout the interior, including dual-firmness Tuscany all-leather seats (available as heated and ventilated) that are specially tanned for a softer feel. Spray-skinned urethane/natural grained surfaces on the door and instrument panel ensure an inviting tactile touch, as do the headliner and interior pillars, which are soft backed and covered with a Monaco woven fabric.

Interior features and/or offerings on the STS include:

• Seat design that has been optimized using a dual-firmness strategy (pillow-like upper; firmer seat cushion) to achieve luxurious comfort as well as outstanding support.
• Available heated and ventilated seats.
• Two wood trim packages incorporating eucalyptus wood. Depending on choice, wood applications are found on the center stack, console, IP molding, steering wheel, shifter knob, and door pulls.
• An aluminum trim package includes aluminum applications on the center stack and console.
• Power seat adjustments for the driver and front occupant provide eight-way seat adjustment with four-way power lumbar and articulating head restraints. In addition, an available memory package provides presets for two drivers, including settings for eight-way power driver/passenger seats with an easy exit driver seat; outside rearview mirrors; power tilt and telescoping steering wheel position with easy exit; and radio and climate control settings.
• Analog instrumentation is defined by bright accents and includes speedometer, tachometer, fuel gauge and engine water temperature. The Driver Information Center (DIC) is displayed in the gauge cluster, and has six-language capability (English, French, German, Italian, Japanese and Spanish).
• An available leather-wrapped heated steering wheel.
• A standard electro chromic (light-sensitive auto dimming) interior review mirror is integrated with OnStar controls.
• An optional convenience package, which includes universal transmitter garage door opener, cargo net and tie-downs.

Interior color and trim offerings on the all-new STS include:

• Nuance leather seating surfaces or available Tuscany all-leather seats.
• Two tone light gray/ebony.
• Two tone light cashmere/medium dark cashmere.
• All-ebony.

SAFETY: OUTSTANDING STRUCTURE, OCCUPANT PROTECTION

The all-new 2005 STS maintains Cadillac’s long-standing reputation for delivering a safe occupant environment in premium vehicles.

Structural enhancements found on the STS contributing to its excellent crash performance include:

• A two-piece magnesium cross-vehicle structure for side and front crash protection.
• Octagonal engine rails to enhance high-speed offset crashworthiness and occupant protection.
• A one-piece hydroformed A-pillar/roof rail structure that brings added upper structural rigidity and enhanced strength during side and frontal impacts.
• Inner and outer rocker panels constructed of strong, ultra-high strength steel – 120 kilograms-per-square-inch yield strength – to enhance occupant protection in a crash event.
• Longitudinal rails injected with 24-pounds per cubic foot of structural foam to protect and maintain their geometry during a crash event. The foam adds to overall body structure stiffness and contributes to preventing intrusion around occupants’ feet during high-speed offset impacts.
• Rear rail inner sections are constructed of high-strength dual phase steel – a first-time application on the Sigma architecture. Dual phase steel brings outstanding characteristics for supporting crashworthiness deformation.

Other occupant protection features found on the STS:

Air bags
The STS has a total of six air bags offered as standard equipment, which help to maximize protection in high-speed crashes while minimizing the risk of injury to out-of-position occupants. Air bags include:

• Driver’s Front Air Bag (dual stage).
• Front-Passenger Air Bag (dual stage).
• Driver’s Side Seat-Mounted Air Bag (thorax protection).
• Front-Passenger Side Seat-Mounted Air Bag (thorax protection).
• Driver Side Roof Rail Side Curtain Air Bag (head protection front and second row coverage).
• Passenger Side Roof Rail Side Curtain Air Bag (head protection front and second row coverage).

When the air-bag system’s central control unit, the Sensing Diagnostic Module (SDM), detects an impact, it determines whether the crash is severe enough to trigger a deployment, and whether the primary amount of inflation is sufficient or if both primary and secondary stage inflation is required. The primary stage alone will deploy in most frontal impacts requiring the supplemental protection of an air bag, while the secondary stage also will deploy in very severe frontal collisions.

The SDM also detects side impacts and determines whether the rail-curtain and side seat-mounted (thorax protection) air bags should deploy. These air bags act like a protective curtain, unfolding from the roof rail between the A and C pillars. When the bag deploys, it is biased toward the window to help maximize protection.

Safety belt pretensioners
The SDM also activates the safety belt pretensioner, which reduces slack in the safety belt webbing. This helps secure occupants in the seat to better hold them in position so they decelerate at the same rate as the car.

The safety belts are equipped with “frictionless” D-rings and low-effort retractors so there is minimum pressure on the occupant, making them more comfortable to wear. The retractors also are energy absorbing.

Rear safety belt features
Second row seats have three-point safety belts in all positions. An added feature is a dealer-available comfort guide on the outboard seatbelts. This device provides better shoulder belt position and comfort for children.

The second-row seats of the STS come equipped with the LATCH system to simplify child seat installation. These anchors, which are secured to the body structure, are provided in all three rear-seat positions.

Security features
Occupant security is provided with a number of standard and available features, including:

• Child security door locks so a parent can choose to prevent their child from opening the rear doors from the inside.
• Power window lockout so control of the windows can be limited to the driver controls.
• Standard engine immobilizer and theft deterrent system.
• Delayed entry lighting, which keeps the interior lights on after the driver enters and until the vehicle is started.
• Standard Remote Keyless Entry also includes a panic button on the key fob, which turns on all the lights except the headlamps, sounds the horn and activates content theft deterrent and anti-lockout features.
• Battery rundown protection automatically shuts off any electrical system inadvertently left on after a period of time before the battery runs down.
• Child entrapment release lever in the trunk.
• Tire pressure monitoring system.

BALANCED RIDE & HANDLING: COMFORT WITHOUT COMPROMISING PERFORMANCE

While the all-new 2005 STS is true to the Cadillac’s performance-oriented roots, a host of chassis refinements ensure that it hits the “sweet spot” of ride and handling. The result is a ride that keeps drivers fresh and comfortable without sacrificing the driving experience.

Road impacts and other harsh inputs are effectively absorbed and dissipated through ride-tuned tires, dampers, suspension components and bushings, as well as improved structure in body-to-chassis interfaces and additional refinements in the engine mounts.

Independent SLA front suspension
Among the many refinements found in the front suspension components is the use of aluminum for both the upper and lower control arms, knuckles, and brake calipers, reducing overall mass and contributing to nimble handling and dynamic wheel control. Reduced unsprung mass requires less damping and provides better road-holding ability.

Hydraulic control arm front bushings also are used for good motion control and to minimize high-speed road vibration by damping energy transmitted to the vehicle structure. A hollow front stabilizer bar on all models brings weight savings and added stability.

Front shocks on base models are monotube dampers from Sachs, a leading German producer of high-performance shock absorbers, which provide highly responsive damping of road inputs. The STS also offers the award-winning Magnetic Ride Control (MR).

Multilink rear suspension
The fully independent multilink rear suspension with fully isolated sub frame is an uncompromising design with excellent suspension kinematics that enables outstanding ride and handling performance.

At the same time, the other features of the suspension architecture give it the ability to control loads and maintain stability during dynamic driving situations, striking a balance between ride quality and high-performance handling capability.

Other rear suspension features include:

• Aluminum upper control arms, knuckles and brake calipers.
• The rear suspension is fully isolated to reduce road and driveline noise.
• Hollow rear stabilizer bars bring weight savings and come in three sizes, depending on the model.
• Nivomat load-leveling shocks, a fully automatic hydraulic level-regulating system with integrated shock absorber, adapt automatically to different loads and road conditions.

Up-level vehicles are equipped with MR shocks, which also incorporate an air pressure system that automatically levels the vehicle in response to the payload.

Enhanced body structure impedance at chassis attachments
All chassis-to-body structure interfaces (i.e. suspension brackets or cradle attachments) on the STS have been redesigned to ensure improve stiffness and structure, thus attenuating low-frequency noise into the cabin. The result is excellent isolation from all such interfaces.

Each of the interfaces have been essentially “tuned” through shape or material thickness (primarily steel) to ensure a robust, stiff structure that effectively minimizes vibrations and related transfer of noise from road irregularities, engine, prop shaft, and other inputs.

Refined six-point front cradle
The engine cradle on the STS, which is solid-mounted to the engine rails for more precise feel, has high stiffness for noise isolation and optimum handling and safety performance. It has six attachment points (two more than typical for a performance sedan) to better handle heavier drive loads and energy pulses, especially in V-8-equipped versions.

As a further refinement, the middle mount (referred to as the number two mount) on each side of the cradle is constructed of cast steel and aligned with the second engine mount (the engine to cradle interface) and front suspension control arm. This refinement ensures the elements in the middle portion of the cradle are extremely stiff, a quality that:

• Effectively reduces noise and vibration transferred through the control arm.
• Attenuates powertrain noise transferred into the cabin, resulting in a significant improvement in powertrain sound quality.
• Reduces exhaust noise transferred into the cabin due to less manifold and pipe vibration.
• Reduces overall noise and vibration from the front cradle and surrounding area.

ZF Servotronic II steering gear
Steering input to the driver and handling are enhanced due to a premium ZF Servotronic II rack-and-pinion speed-sensitive steering gear (optional) with 18.2:1 variable ratio, speed-sensitive variable assist, and a turning radius as little as 11.5 meters.

The ZF steering system incorporates outstanding torsional stiffness with less operating friction. The result is steering which is very precise, with highly linear response and extremely smooth, predictable transitions.

Magnetic Ride Control
One of the most distinguishing ride and handling features of the STS will be the optional Magnetic Ride Control (MR) system. This technology, which uses electronic control of damping forces in a continuously variable real-time damping system to provide exceptional responsiveness, greatly increased driver control and increased tire contact with the road, regardless of road surface.

In addition, the MR system on the STS is among the first to make available two selectable settings accessed through the infotainment display head – a performance or touring mode.

The performance mode may be used where road conditions or personal preference demand more control; the setting provides more “feel” or responsiveness to road conditions. The touring mode is available for normal city and highway driving and provides a smoother, more accommodating ride.

The MR system uses valve-less damping and magneto-rheological fluid technology. The fluid is a suspension of iron particles in a synthetic hydrocarbon-base fluid. When the system is activated, the particles are magnetized and aligned into fibrous structures, changing the flow resistance of the fluid rheology. By controlling the current to an electromagnetic coil inside the piston of the damper, the system varies the fluid viscosity continuously in response to road surface conditions over a broad damping range.

Damping levels are adjusted up to 1,000 times per second, making the system exceptionally responsive and providing increased wheel contact on even the roughest road. Reduced wheel bounce ensures an even ride by virtually eliminating heave, pitch and roll. It also delivers excellent roll control during transient steering and evasive maneuvers.

A set of wheel-to-body sensors detects changes in the road surface and the system controller adjusts the fluid viscosity to vary the damping force accordingly, providing a flatter ride during cornering and reduced diving or squatting during braking and acceleration.

StabiliTrak system
The standard StabiliTrak system on the STS is a sophisticated four-channel (independent control to all four corners of the vehicle) active handling system. It links the vehicle’s dynamic control systems to assist the driver in maintaining control under demanding or adverse conditions such as wet, snow-covered or icy roads, tight turns, and evasive maneuvers.

In effect, the StabiliTrak system determines the driver’s intentions and optimizes overall vehicle control to keep the dynamic forces within safe limits in any driving situation – and it does it in a non-intrusive manner so the control seems almost intuitive.

Brake system
The STS is equipped with four-wheel-vented disc brakes with standard four-wheel antilock braking system (ABS) and traction control system (TCS). The brakes feature vented rotors consistent with the demands of a luxury performance sedan, and aluminum calipers (twin-piston front, single-piston rear) to reduce weight. Base brake package rotor dimensions are 303 x 32 mm front and 298 x 26 mm rear. Uplevel brake package rotor dimensions measure 323 x 32 mm front and 320 x 26 mm rear.

Panic Brake Assist (PBA), which senses emergency braking by detecting the speed or force the driver applies to the brake pedal and boosts the power as needed, is incorporated into the brake system. Under certain conditions, the panic brake assist may activate the ABS more quickly and easily than vehicles without the feature, potentially reducing overall stopping distance by eliminating the delay caused by not braking hard enough and/or soon enough.

The system also features Dynamic Rear Brake Proportioning, which regulates braking pressure to optimize stopping distances and control under all vehicle-loading conditions.

Wheels and tires
The STS is available with 17- or 18-inch wheels. The following wheel and tire packages include:

Michelin Energy LX4, all season luxury touring 235/50R17
17 x 7.5 cast aluminum wheels at all four corners

Michelin Pilot HX MXM4, all season performance, V speed rating
Front - 235/50R17, 17 x 7.5 cast aluminum wheels
Rear - 255/45R17, 17 x 8.0 cast aluminum wheels

Michelin Pilot HX MXM4, all season performance, W speed rating
Front - 235/50R18, 18 x 8.0 flow-formed aluminum wheels
Rear - 255/45R18, 18 x 8.0 flow-formed aluminum wheels

Michelin Pilot Sport, summer only high performance, Y speed rating
255/45R18; 18 x 8.0 flow-formed aluminum wheels at all four corners

Story by Cadillac Edited by Maximum-Cars.com