In Minnesota you pay twice as much tax on diesel as gasoline, so I'm not sure what kind of tax credit makes up for that. Also most of the Euro diesels can't meet our emissions laws. That's why the VW TDI's weren't available for a year or two. VW needed to get their stuff together. Catapillar got out or will be getting out of the semi engine business all together. Not worth the hassle of trying to meet emission laws.