The reason they designed these cars was NOT due to gasoline efficiency issues but for profit. Loading them down with luxury items like leather, etc heightened their profits.
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Well, duh. They peddled trucks because trucks could guzzle and not bring down their CAFE averages for cars.
They made bazillions on these ugly things, but they had to know that the day of $3.00 gal. gas would bite them in the butt someday. AS usual, it bit the workers' butts, not the executives'.
Roger Smith got a nice fat raise every year he was pres. of GM.
Every years, they lost market share.
Every years they built crappy cars. legendarily crappy cars.
By the time the got the bugs out of the Olds Diesels and the Caddy Allante, no one wanted to touch them.
There was never a reason to touch a Cadillac Cimarron.