Major changes went beneath the hood of the 1993 model, which went on sale in January 1992. Cadillac installed its 4.6-liter Northstar V8 engine, which also went into the 93 Eldorado and Seville. The new dual-overhead-cam V8 made 95 more horsepower than its overhead-valve predecessor and drove a new electronically controlled 4-speed automatic transmission. A new traction control system could simultaneously apply the brakes or shut down engine cylinders, to minimize front-tire spin. It worked at any speed. Previous traction control had acted upon braking only, and was inactive above about 30 mph. A new Road Sensing Suspension had sensors at each wheel, to read the road by measuring wheel position and body motion, automatically adjusting suspension damping. The system reacted in fractions of a second and replaced a simpler Speed Dependent Damping system that switched among three firmness settings according to vehicle speed. The rear suspension was redesigned and new all-season tires were rated to 155 mph. Also n