The theme of the American Dream is inverted in Chapters Three and Four of "The Great Gatsby" as the reader perceives the decadence of the Jazz Age that Gatsby and his wealthy friends live in as well as the corruption that revolves around them. As symbols of wealth, Gatsby's house and car figure into the tableau of decadence, corruption, and power that money brings.
That Gatsby's house is located in West Egg rather than the estblished East Egg where "old money" lives is significant:
East Egg condescending to West Egg, and carefully on guard against it spectoscpic gayety.
West, traditionally, is symbolic of death, the end of the day. With the cars, too, death passes through West Egg. In Chapters 3 and 4, for example, automobiles come and go "like gypsies," bringing in people--strangers--to Gatsby's parties. Even a hearse and a limousine are included: the physically dead and the morally dying.
On the other hand, Gatsby's car takes on a mythological property as it is described like a god's chariot with its
triumphant hatboxes and supper-boxes and tool-boxes, and terraced with a labyrinth of windshields that mirrored a dozen suns.
One thinks of Apollo, the sun god, or Icarus, who flew too close to the sun as the car has "fenders spread like wings." With these descriptions, the illusionary quality of the opulence is apparent. This car, too, represents decadence and corruption. It is cream-colored--later it is referred to as yellow when it becomes the "death-car"--and it has green seats, both the color of money. The cars, the bootlegged alcohol, the freedom of the women all contribute to the falseness of the American Dream. For Nick, Gatsby comes alive as the American Hero, "delivered suddenly from the womb of his purposeless splendor." There is a fragileness and a falseness to his dreams.