Engineering:Speed Dependent Damping Control

Speed Dependent Damping Control (also called SD²C) was an automatic damper system installed on late-1980s and early-1990s Cadillac automobiles. This system firmed up the suspension at 25 mph (40 km/h) and again at 60 mph (97 km/h). The firmest setting was also used when starting from a standstill until 5 mph (8 km/h). Applications:

• 1989–1992 Cadillac Allanté

Computer Command Ride

The semi-active suspension system was updated as Computer Command Ride in 1991. This new system included acceleration, braking rates, and lateral acceleration to the existing vehicle speed metric.

• 1991– Cadillac Fleetwood
• 1991– Cadillac Eldorado
• 1991– Cadillac Seville
• 1991– Cadillac De Ville (optional, standard for 1993)
• 1992– Oldsmobile Achieva SCX W41

References

• Daniel Charles Ross. "Cadillac Allanté". Motor Trend (February 1989): 88–93. 
• Robert J. Reuter (1989-02-01). "Speed Dependent Damping for the 1989 Cadillac Allante". SAE Technical Paper Series. 1. doi:10.4271/890178. SAE Technical Paper 890178. http://papers.sae.org/890178/.