The real efficient car and truck combinations have always been sold on the world market, but the average American consumer does not know, and as long as fuel is cheap, doesn't care. It wasn't until we got confronted with $5.00/gal fuel and stagnant wages we woke up. Realistically, we don't need the ultra heavy, big power trucks that are being sold right now, because unless you tow heavy or earn your living with a unit like that, it's a huge waste of money. And the new smaller diesels that are coming out for the light trucks are excessively complicated. Just look at that new small V8 Duramax and Cummins motors, and now the 6.7 Ford. On the world market they already have engines in the 4-6 cylinder range that meet stricter clean air requirements and are simpler.
For too long engines have been built around the fuel, and not the fuel reformulated for the engine. If the oil companies were forced to adjust their chemistries so that the fuel reacts completely inside the engine and not partially, then all the reasons for current engine design would cease, mpg would skyrocket, and engine life would triple. Forgive my rant, but I am personally tired of having to build and design things that these idiots have had the capability of doing for more than an ice age.