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New Car/Review

The Cadillac STS, An Executive Jet

by Larry Weitzman


SEE ALSO: Cadillac Buyer's Guide

The Cadillac STS (Seville Touring Sedan) came to life about 10 years ago in the third generation of this Seville platform. It was a handling package added to the standard Seville. The new Seville is actually in its fifth generation starting with the 1998 model year and in its third generation as an STS.

The original Seville concept started life in 1976 as a smaller Euro styled sedan. It has gone through several changes until 1991 when the fourth generation was unveiled in early 1991 as a 1992 model. It was designed without compromise by a small design team headed by Dick Ruzzin (his reward was being named head of GM Europe). The result was an instant success and it was considered one of the most beautiful sedans ever created. It was powered by Cadillac's 4.9L 200 hp pushrod V-8.

The STS was a sportier version of the Seville, with upgraded suspension, nicer interior appointments and crisper handling. In 1993, the STS received Cadillac's long awaited Northstar V-8. A state of the art engine with dual overhead camshafts, 32 valve technology and very high output. It developed 275 hp out of 4.6L. With this engine, Cadillac vaulted to the front as a leader in engine technology and development. It had new to the industry features such as a limp home mode in case of coolant loss and 100,000 mile tune up intervals.

In 1998, the Seville received a significant makeover. The car's basic shape was retained, but the body structure was improved, the wheelbase lengthened (1.2 inches) and the track was widened. But overall length actually went down about 3 inches (now at 201 inches). It is for all intents and purposes a new car. Retaining and refining the basic exterior lines have added to the beauty of an already world class looker. This car is as beautiful as it is unique. I thought it was the best looking car in 1992 and with the 1999 model, it remains at the top of my very short list of great looking cars. It is sleek, crisp and clean with perfect proportions. There is almost no chrome or bright metal trim necessary to show off this design.

The refined Northstar V-8 now produces a class leading 300 hp at 6,000 rpm and 295 lb-ft of torque at 4,400 rpm. The SLS (Seville Luxury Sedan) retains the 275 hp version of the Northstar. It is one of the smoothest and quietest engines I have ever driven and is definitely world class.

You would only imagine great performance from an engine like this and it delivers big time. Accelerating to 60 mph from a standing start takes a scant 6.7 seconds, with one run at 6.21 seconds. Passing is exhilarating. 50-70 mph averaged only 3.5 seconds and the same acceleration up a 6% grade averages a quick 4.6 seconds. There has never been a Cadillac sedan like this one when it comes to performance. In fact there aren't many sedans that measure up to this kind of performance.

The engine also produces some of the sweetest sounds to come out of a luxury sedan. Even though it is whisper quiet at cruise, it comes on the "cam" with a throaty growl that would make any racecar proud. Many times I found myself hard in the throttle just to listen to the engine. It's that good.

The numbers only tell part of the story about this remarkable automobile. The STS drives through a silky four speed automatic that has a continuing shift algorithm that selects shift points and the proper gear depending on how your driving the car. It has accelerometers that analyze braking and cornering forces to instantly determine the appropriate gear. It does work and during hard acceleration, it lets the engine run to its redline (6,500) to achieve maximum performance. Needless to say, this is a marvelous powertrain. I would like to see the transmission with five speeds instead of four. It would expand the performance envelope, possibly without a fuel economy penalty.

When driving the STS hard at Willow Springs, I noticed that I didn't need to use hard throttle applications to stay in lower gears when coming out of corners, it sensed what gear I wanted at all times. It was truly automatic. During normal driving a driver will never know or be aware of this incredible system. It is superb.

The STS also comes with another advanced feature called "Stabiltrak". It combines a yaw rate sensor and a lateral acceleration sensor with the car's ABS, steering, suspension and traction control to improve directional and stability. If Stabiltrak senses the car is not going where the driver is steering it to go, the Stabiltrak computer sends a series of directions to the traction control and ABS to keep the STS on its desired course.

A few laps at Willow Springs also proved to me how valuable this system is when pushing the car very hard. It too works exactly likes it's supposed to. Amazing stuff.

Driving in our neck of the woods, here in El Dorado County, I couldn't think of a more pleasurable mode of transportation. This STS has a hunkered down feeling. It goes around corners like it is literally glued to the road. Green Valley, Bass Lake and the roads of Apple Hill were as fun as it gets. The grip from the 16 inch 235/60 series Z rated tires is tenacious. This is a real road machine that is effortless to drive quickly. It inspires confidence and safety (front and side airbags are standard).

Ponderosa Road was as smooth as I have ever encountered. It handles dips, bumps and washboards like no other car. The fully independent suspension is state of the art with something added, a continuously variable road sensing system that adjusts damping rates at each corner in real time. Rolling smoothness, insolation and impact feel are exceptional. There are no creaks and rattles.

On the highway (or anywhere else for that matter) it doesn't get smoother or quieter. This may be the best road car I have ever driven. There is absolutely no wind or road noise. It turns tar strips and concrete into glass. Part of the reason is that new construction techniques have increased overall body rigidity and stiffness by over 50% from the previous generation.

The variable assist rack and pinion power steering had excellent on center feel, with the appropriate higher effort in spirited driving and reduced effort in low speed handling. It is natural feeling and even with front wheel drive there is no torque steer in normal driving. Hard acceleration will elicit only the smallest hint of torque steer and only in certain situations. Torque steer has been all but eliminated.

So the STS has world class performance, ride and handling, but what about the passenger compartment and appointments. My test vehicle was wrapped in soft, black leather. The seats, the doors, and part of the steering wheel (only part because half of the wheel is gorgeous zebrano wood which also decorates the center console, shifter, dash and doors).

The seats are large and have an adaptive seating system, which if engaged will conform the seat to your body. They are comfortable. New for 1999 is the massaging lumbar seat that will activate a series of rollers to move up and down inside the seat to reduce fatigue and stress ($200 option).

The rear accommodations are superb for two with more than ample room, less so for three. There is a trunk pass through for skis behind the rear center armrest. The center sections of all seats have breathable perforated leather.

The dash is outstanding. Instead of attempting to "out button" the competition, it is a marvel of style and simplicity. The instrument pod contains a vacuum fluorescent display (looks like a hologram) of a large tach and speedo left and right flanked by a temp and fuel gauge. It is beautiful. Beneath is a trip computer and other driving information controlled by two sets of three buttons to the left and right of the pod. The dash and sides of the console are covered in a thick, dense material.

The vertical part of the center console contain the superb 425 watt Bose sound system and electronic HVAC controls with separate temperature for the passenger and driver. The armrest beneath the center console holds the 6 disc CD changer. If I were to nitpick this car, it would be that the armrest on the center console could use a little more padding. There is almost no hard plastic in this car, even the windshield "A" pillars are padded. All the switches, controls and buttons have a quality feel.

I found the fit and finish, especially on the inside to be excellent. The people at Cadillac can stand proud next to the STS. I have driven lots of cars in my life and this one ranks at or near the top. It is near perfect in so many aspects. It just feels good.

My wife, Kim, enjoyed some more mundane features. She really liked the auto door locks that also auto unlock. She also appreciated the way the remote trunk release opens the trunk fully. She too commented on the remarkable quiet and smoothness of the STS.

Now for the problem and it's only money. The "base" price for the STS is $47,850 plus $670 for destination. In addition, my test vehicle had several options including the adaptive seating package ($1,627), beautiful seven spoke chrome wheels ($795), in console CD changer ($500), wood trim package ($595) and the bargain, Z rated Goodyear Eagles tires ($250) for a total of $52,287.

An SLS can be had with comparable equipment for about for about $5,000 less. Its base price is $44,025 with destination and comes standard with Stabilitrak, road sensing suspension and most other STS features but with the 275 hp Northstar engine. Because of a different rear axle ratio there is a small difference in off the line performance, but passing would be about the same.


Price                         SLS      $43,355
                              STS      $47.850 to about $52,000
Configuration                          Transverse front engine
                                       front wheel drive


4.6L, DOHC, 32 valve          STS V-8  300 hp @ 6,000
                                       295 lb-ft of torque @ 4,400 rpm
                              SLS      275 hp @ 5,600 rpm
                                       300 lb-ft of torque @ 4,000 rpm

                                       4 speed electronic 
                                       automatic with performance 
                                       algorithm shifting


Wheelbase                              112.2  inches
Length                                 201.0  inches
Width                                  75.0   inches
Height                                 55.4   inches
Weight                                 4001   pounds
Fuel Capacity                          18.5   gallons


0-60                                   6.7    seconds
50-70                                  3.5    seconds
50-70  uphill                          4.6    seconds
Top Speed                              Electronically governed at 150 mph
Fuel Economy                           EPA 17/26 city/highway.  I averaged about 18 mpg in
                                       very spirited driving, I would expect 19-20 mpg in
                                       El Dorado County and 26-28 mpg on the highway.