The debate about whether diesel or petroleum fuel is best continues on, as fuel costs and vehicle price tags are fluctuating factors. However, when it comes to fuel economy diesel is typically the victor. This much is true especially for the 2013 Volkswagen Beetle TDI, which was just rated as the most fuel efficient convertible in America, at least on the highway, according to AutoBlog.

The diesel-powered car gets an impressive 41 miles per gallon on the highway, the best among comparable cabriolets. In fact, the Smart Fortwo drop-top is the only one that comes close with a 38-mpg highway fuel economy, Motor Trend reports. While the Volkswagen has the best highway mileage, it only gets an estimated 21 mpg in the city. This translates to a combined fuel economy of 32 mpg, which is less impressive than the Smart Fortwo's 36-mpg combined rating. The latter car has a city mileage of 34 mpg.

Drivers looking for a car they plan on driving almost exclusively on the highway may be interested in the Beetle TDI's impressive mileage. But those who plan to spend at least some time on city streets may want to consider other fuel efficient options.

Car shoppers looking for a car with a decent fuel economy may want to head over to New Jersey State Auto. The dealer carries a wide selection of makes and models. Drivers will be able to find cars of all kinds here, even if they are looking for an alternative fuel model, such as a Toyota Prius of a diesel-powered car. Plus, every model on the lot is CARFAX certified, so buyers know they'll be driving away in a reliable ride.