The drag coefficient (Cd) for a 2008 Chrysler 300 isn't readily available from a single, definitive source. Automakers don't always publish this data for every model year. While some sources might cite a value, it's likely an approximation or derived from testing done by third parties, and may vary slightly based on the specific trim level and options.
To find a potential value, you would need to search automotive testing websites or publications that specialize in aerodynamic testing. Even then, you may not find an exact number for the 2008 model year.
