During several scenes it shows Steve and Officer Banner in two different kinds of cars. One scene shows them in a Ford LTD and than in the next scene right after that it shows them in a Plymouth.
Noah Berry Jr. (Officer Banner) is a senior police officer, but one uniform shirt that he's wearing shows only 3 service stripes (1 = 5 years of service) and his other shirts shown have 6 service stripes.
As noted previous there are actually three different police cars driven by Austin and Banner, i.e. a Dodge, a Ford LTD, and an AMC Matador (probably a leftover from Adam-12, also filmed at Universal Studios.