In an attempt to meet consumer demand for fuel efficient vehicles and comply with the 2016 CAFE, or corporate average fuel economy, standards, automakers are ramping up efforts to improve fuel economy across their fleets. The result is a steady gain in miles per gallon across the industry.

TrueCar.com tracks fuel economy by collecting data from brands, manufacturers and the U.S. Environmental Protection Agency. The June numbers show a 0.7 mpg improvement last month compared to June 2012. The industry average hovers around 23.7 mpg for cars and trucks, which held steady from May. U.S. manufacturers saw the biggest month-over-month gains, as the TrueMPG went from 22.0 mpg to 23.1 mpg in June.

"Despite the relative drop in gas prices, consumers' preference for fuel efficient vehicles only grew stronger in June," said Jesse Toprak, TrueCar's senior analyst. "Even though we observed unseasonably strong increase in truck sales in recent months, the higher efficient of the new models resulted in another month of improvement in overall TrueMPG for the industry."

While the report focuses on new cars, drivers in the market to purchase used cars, trucks or SUVs can still find models with great fuel economy, including hybrids like the Toyota Prius. The TrueMPG provides an average, which includes vehicles with high mileage and those with lower mileage. This means drivers will have plenty of vehicles to choose from that are a few years old but still get more miles per gallon than some new cars on the market. To find a great ride, car shoppers can head to New Jersey State Auto Auction, which has a wide selection of makes and models to choose from.