Recently, Chevrolet announced that its new 3-liter, six-cylinder diesel engine, custom-designed for the job, would bring fuel economy of 23 mpg city, 33 mpg highway, to the Silverado. Can Ram beat that with its newly upgraded 3-liter V6 diesel? The answer: No, but it comes awfully close—falling...

The Wrangler has long been criticized for its low gas mileage — though, when it had competitors such as the FJ Cruiser, they had roughly the same mileage. It seems it’s hard to make a go-anywhere 4x4 that can stand up to the worst trails, remain stable on the highway, and pass all the safety...