 The largest difference is the interior design differences 9C3 is intended for undercover or supervisor use, and typically features a more consumer-oriented interior starting with the 8th generation Impala in 2001 all the way to the 9th generation Impala Limited.This police package code was originally offered with the Chevrolet Lumina's 1st generation model starting in 1992 & again with the 2nd generation in 1995 as the mid size front wheel drive alternative to the rear wheel drive Caprice sold between 1991 & 1996.The Caprice PPV was offered with a 9C3 package from 2011 to 2013.