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2006 Cadillac STS-V review: 2006 Cadillac STS-V

The 2006 Cadillac STS-V is built like a tank, goes like a train, and drinks like a fish. A comfortable, tech-laden cabin and blistering top-end performance make this car a serious contender on the sports sedan stage.

Kevin Massy
8 min read



2006 Cadillac STS-V

The Good

The 2006 Cadillac STS-V comes with an arsenal of standard onboard tech including navigation, Bluetooth integration, and a symphonic audio system. Its well-appointed cabin is a nice place from which to watch the freeway fly by.

The Bad

The STS-V's arcane voice-recognition system requires a course of study to master and even then works indifferently. Its substantial curb weight and supercharged V-8 are not built for the city, and the Caddy drowns the sorrows of urban driving in gallons of premium 91.

The Bottom Line

The 2006 Cadillac STS-V is built like a tank, goes like a train, and drinks like a fish. A comfortable, tech-laden cabin and blistering top-end performance make this car a serious contender on the sports sedan stage.

Photo gallery:
2006 Cadillac STS-V

When the nice man from Cadillac dropped off the 2006 STS-V at our garage, he told us that the "V" emblazoned on the car's front fenders stands for Velocity. After a week with the Caddy's flagship sports sedan, we can see why. With its 468-horspeower Eaton-supercharged Northstar V-8 engine, the 2006 STS-V is the most powerful Cadillac ever to roll off GM's production lines. Nevertheless, Velocity was not the first thing that sprang to mind when we took possession of our Light Platinum tester.

From the outside, the STS-V presents an imposing spectacle: an aggressive square-jaw front-end is dominated by two huge chrome mesh intakes that enable it to inhale air for the supercharger. Square headlights and a clunky front bumper add to the car's boxy, tanklike profile. Inside, the interior appointments are far more in line with luxury and comfort than with the Spartan, rugged interior accents traditionally associated with performance driving. The STS-V's sumptuous eight-way power front leather-and-suede seats would double as armchairs in most family rooms, particularly with their built-in shoulder speakers. Other materials in the cabin continue the luxury theme, with olive ash wood providing the trim for the center console, doors, and shifter, and mock carbon fiber accentuating the heated leather steering wheel, and sweeping across the dash.

Speakers in the shoulders of the front-row seats are among the 15 that make up the STS-V's audio system.

The matte black plastic for the head unit is a bit down-market compared with the rest of the interior, but this was quickly forgotten when we set eyes on the STS-V's huge in-dash tilting touch-screen LCD display. The main function of the display (which can be programmed with one of three background colors) is as an interface for the STS-V's advanced DVD-based GPS navigation system.

Navigating the navigation system
Although the display shows maps clearly, the navigation system's processing speed is sluggish. When zooming in or out, the map takes at least a couple of seconds to refresh, and most inputs are greeted with some kind of whirring or ticking sound as the unit thinks about its next screen. Those who have not read the instruction manual will find using the navigation system a challenge as the destination-entry screen displays a bewildering array of icons without any text explanation as to what they are for. These symbols include: a letter; the Statue of Liberty; an arrow; a house brick; a phone; a balloon; a road being struck by a bolt of lightning; a target; a globe; a hazard symbol; and a stack of paper.

Taking a wild stab in the dark, we surmised that the letter icon must be the means of programming a destination by address, a leap of faith that proved inspired as it brought up an on-screen keypad that allowed us to program in our address with ease using the large virtual letters. With our destination entered, the STS-V's navigation system provided clear turn-by-turn voice guidance to our destination in the same clipped, British accent that we found so diverting in the 2006 Range Rover Supercharged Sport. In addition to a street address, the system accepts destination entry via point of interest (Statue of Liberty button); intersection (house brick button, which is actually a stoplight); or by entering a destination directly onto the map (arrow button).

Navigation was easier to program using the touch screen than the voice commands, but only just.

Additionally, the navigation system can be controlled using voice commands, which are initiated using a button on the left-hand side of the steering wheel. For specific voice commands, we were compelled to look in the manual, where we found the list of accepted formats for controlling the navigation system, the stereo, the Bluetooth hands-free calling interface, and the HVAC controls.

While the STS-V is unable to process destination-address entry via voice command (in the vein of some Honda cars we've seen), its navigation system does boast some very useful voice-command features, including: on-demand repetition of turn-by-turn guidance (say: Navigation repeat) and the ability to overlay points of interest on the map (say: Navigation Japanese restaurant, for example).

Voice commands also can be used to make phone calls via the STS-V's standard Bluetooth hands-free calling interface. Pairing our phone to the system was very straightforward using the CONFIG hard button on the head unit. Car and phone found each other immediately, and we were then able to make calls either manually via the touch screen keypad (which is curiously called up by pressing the AUX button); or by voice dialing (say "telephone enter" to prepare the system to receive spoken numbers).

Despite the ease of pairing, the final stage of placing a call using the voice-recognition system presented us with a challenge: having called out our chosen number, which the system understood and read back to us without any trouble, we were asked if we would like to continue. Our first attempts to confirm ("yes", "continue", "call") all proved incomprehensible to the system, and it was as a last resort that we tried "dial"--which succeeded in placing the call. Another quirk of the hands-free system is that, while calls can be placed without navigating to the Bluetooth keypad screen, there is no apparent way to end a call without using the touch screen. Sound quality through STS-V's front speakers was adequate to understand the caller on the other end of the line, and the car's built-in microphone enabled us to be understood with speakerphone quality.

Bluetooth hands-free calling comes as standard on the 2006 Cadillac STS-V.

The 2006 STS-V scores high on digital audio capabilities; the car comes with an as-standard 15-speaker Bose 5.1 studio surround sound audio system complete with a 6-disc in-dash CD changer. The stereo plays both MP3 and WMA discs, and can support audio and video auxiliary inputs via three RCA jacks located in the center storage compartment. It will even play DVD videos when the parking brake is on. Sound quality is excellent, with built-in digital signal processing enabling drivers to optimize acoustics to their own preferences. The audio system also features speed-sensitive volume to adapt your soundtrack to the racetrack. Using the touch screen, we were able to navigate digital audio files with ease and the advanced display interface in the STS-V was one of the most advanced we've seen in its ability to show full ID3-tag information for MP3 files. The car is prewired for XM Satellite Radio and comes with a three-month subscription as part of the sticker price.

Power and weight ratio
It is perhaps partially due to the wealth of gadgetry onboard that the STS-V is such a porker: weighing in at 4,233 pounds, it is more than 200 pounds heavier than both the 2006 BMW M5 and the 2006 Jaguar Super V8.

Around town the chunky STS-V behaves like a caged lion, with the Northstar growling and grumbling at the limits of its confinement, and the car lunging into corners with torpid understeer. In automatic mode, the engine unhappily upshifts at around 2,000rpm, and the drivers could be forgiven for checking that this is indeed the V version of the STS for which they have paid an extra $30,000.

For reassurance, however, all they need to do is to let the beast loose on the open road. Its heavy steering and heavy frame may disqualify it from being a canyon-carver, but when up to speed, the 2006 Cadillac STS-V is about the most potent sedan this side of the BMW M5 in M Drive. Having fought our way through the city in automatic mode, we decided that a spell of manual shifting was the order of the day for the asphalt of the freeway, and we soon found out where this car is happiest. Having catapulted from 20 to 70mph in second gear along a freeway on-ramp, we were left scratching our heads (virtually you understand--our hands were welded to the steering wheel) at the sheer abundance of top-end power this car has. When pushed to its upper limits, the supercharged Northstar emits kazoolike engine notes accompanied by a supercharger whine that almost encourages the driver to kill the output from the quindecaphonic audio system. We said almost.

For those wanting to add a bit more zing to the plain old experience that the STS-V's 439lb-ft of torque provides, the car has more performance goodies in store courtesy of a competitive driving mode (CDM), which is activated by tapping the Traction Control button twice in quick succession. A feature inherited from the Corvette, CDM disables traction control while adjusting the settings of Stabilitrak intervention to enable drivers a reasonable amount of traction loss before coming to the rescue.

Competitive driving mode adjusts the Stabilitrak settings to enable more slippage.

Without access to a racing track with very wide corners, unfortunately we are unable to provide any useful information on how this feature works in practice. All this fun comes at a price, however, and the STS-V is a thirsty animal. The EPA reckons it gets fuel economy of 14mpg in the city and 20mpg on the freeway. Aside from a few moments of exuberance, we drove the STS-V with considerable restraint over 150 miles of mixed city and freeway driving, and observed an average fuel economy of 13.9mpg.

The STS-V comes with a good array of safety features. GM's StabiliTrak computer-controlled, four-channel stability system applies braking inputs to individual wheels to keep the car going in the direction in which it is being steered, while all-speed traction control adjusts engine power and braking to reduce wheel slippage when loss of traction is detected. Driver and front passenger get dual-stage frontal- and side-impact airbags, and head-curtain, side-impact airbags protect all four outboard passengers. Active safety features include rain-sensing wipers, a tire-pressure monitor for all wheels, daytime running lights, and an ultrasonic rear park distance-control sensor. The STS-V also comes with GM's Intellibeam headlight-control system, which uses a forward-looking digital camera mounted to the front of the rearview mirror to enable the car to turn on its high beam headlamps at night when no other vehicles are detected on the road ahead. One year's worth of GM's OnStar Directions and Connections service also comes standard.

In contrast to the 2007 Cadillac SRX we reviewed earlier this month, the options sheet for the STS-V is mercifully straightforward as everything from navigation to Bluetooth comes as standard. Our tester came with all the features listed above as standard for a total price of $77,090, including a $2,100 gas-guzzler tax and a $720 destination charge.

The 2006 STS-V is proof Cadillac can run with the European competition when it comes to performance and cabin technology, and prospective buyers will likely find themselves considering the 2006 BMW 550i or the 2006 Audi S6 or the 2006 Jaguar Super V8. Ah, the agony of choice.


2006 Cadillac STS-V

Score Breakdown

Cabin tech 9Performance tech 9Design 8


Trim levels BaseAvailable Engine GasBody style sedan