It costs almost nothing...we're talking about engine swaps and dickering with the diesel air pollution controls a little bit.
That's all.
The Big Three should have started offering small and efficient four cylinder diesel models four years ago as an option on most of their midsize and compact cars and minivans.

A guy up in Canada posted a YouTube video about two years ago that showed how easy it was to drop a 1.9 liter VW TDI diesel into a Dodge Caravan. He gets 52 miles per gallon. What soccer mom wouldn't jump at the chance to get that kind of fuel economy?
It would be a bargain even at 40 MPG.

The Big Three could just buy up VW's production of 4-banger diesels right now and have the 2009-1/2 model year sedans and minivans ready to go before spring.

This isn't rocket science.

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