The big news for 1988 was the introduction of the Seville Touring Sedan which came equipped with GM's FE2 Touring Suspension. It featured special 15inch alloy wheels, special springs, rear sway bar, and a special 15.6:1 steering ratio for enhanced handling, a grille mounted Cadillac emblem, special cloisonne trunk lock cover, and a unique four-place interior. 1988 Seville Touring Sedan production totaled 1,499 units. The first 1988 STS's were custom built in June 1988 by Cars and Concepts and announced at the 1988 Detroit Grand Prix. These were available to VIP's within General Motors, the Cadillac Division, some major shareholders and a short list of dignitaries. A special label was affixed to the lower corner of the driver-side front door by Cars and Concepts identifying it as one of the original STS's. 2014 Survivability rate*: 14% (210 remaining).
For 1989, the first "production" STS's were sold to the public as a "Limited Edition" with an option code of YP6. Features from the initial concept 1988 model were carried over to the 1989 LE production model year with the addition of a retuned European-feel suspension package for more precise steering control and firmer feel of the road. The features of the STS over the standard Seville included hand-stitched beechwood ultrasoft leather seats, anti-lock braking, touring suspension, a 3.3:1 drive ratio; 15-inch cast aluminum alloy wheels and Goodyear Eagle GT4 blackwall tires. Additional STS features: Grille with flush-mounted wreath-and-crest, modified driver's front fender with the cornering light moved to the front facia and headlight monitors removed, matching body color front lower airdam and bodyside moldings, matte black export license pocket with bright bead, matte black front bumper impact pads and rear bumper guard vertical inserts, matching body color outside rearview mirrors with black patch, modified (from Eldorado) rear reflexes (moved to the bumper), modified export taillamps with three-color European-style lenses, STS nameplate on the decklid and an STS exclusive cloisonne deck lid lock cover. The STS interior had a 12-way power front seat, manual articulating front seat headrests, center front armrest with cassette and coin/cup storage console trimmed in ultrasoft leather, net-type map pockets, rear bucket seats with integral headrests, center rear console and rear storage compartment, leather-wrapped front and rear door trim panels, door pull straps and overhead pull straps, high-gloss elm burl real wood appliques on door trim panels and switch plates, horn pad and bar, instrument panel and front and rear consoles, Beechwood Thaxton floor carpet and a decklid liner in tara material with STS logo. Other standard STS features (these were options on the standard Seville) were: automatic door locks, illuminated driver and passenger side visor vanity mirrors, illuminated entry system, rear window defogger, theft-deterrent system and trunk mat. Only 4 exterior colors were available for the STS this year: White Diamond; Sable Black; Black Sapphire; or Carmine Red. 1,893 Seville Touring Sedans (STS) were produced for the 1989 model year. The first 1989 STS's were leftovers from the Cars & Concepts run of the 1988 production year and had the special sticker located on the lower part on the inside of the driver's door. These were produced prior to December 1988 for the 1989 production year and are very rare. The last 6 digits of these VIN numbers would be below 808000. As with the 1988 model, a special 3.25" x 2" black/silver chrome label was affixed to the lower inside area of the driver-side front door by Cars and Concepts identifying it as one of the original STS's{ref 7} As of 2014, the survivability rate* of this 1989 model is at about 3% (approximately 57 remaining) per the NHTSA and Broxterman Auto Survivability Rate Chart - BASRC).