Hear that? That's a sound you haven't heard from a Chevy car in a while. In my 17 years of test drives this is the first American car I've had with a Diesel engine. But the headline here is 46mpg highway and it comes courtesy of the Chevy Cruze.When 50-state compliant diesel engines began showing up a few years ago, the push was primarily engineered by the VW Group. Gas prices were sky high and alt fuel vehicles were in consumers’ minds. So Chevy decided to see how a small diesel-powered car would do against competitors’ hybrids and other diesel models.