Conclusion: If you want a car with the best fuel efficiency around, there are other options you can consider that are available now.  You can choose a car with manual transmission over automatic transmission.  Also the way you drive influences and the way you maintain your car influences the gas mileage you get.  The Gassy Cow has a list of gas saving tips.  But if the automakers wanted to make truly efficient cars that are good for the environment, they should make small, hybrid diesel cars what can run on biodiesel fuels.  The automakers don't make such a vehicle yet.  Actually, diesel and hybrid are treated as rival mutually exclusive technologies. 
 

But automakers are in the business to make a profit.  Large cars simply make more money for the automakers.  They won't produce them if the public doesn't demand them So, we (the car buying public) should demand that the automakers should create small, diesel-hybrid cars.  If we demand that they make them and buy them in droves once created, then being smart businessmen they will do what we ask.  So, I think, you should write (or email) the car makers and ask them to create and release as soon as possible. Small Hybrid-Diesel Cars.  OK, OK, some of you have larger families and don't want a small car.  I understand, for you just demand Hybrid-Diesels that run an bio-diesel fuel :-)  Find below the mailing addresses of the big three (well there are really two now) U.S. car makers.

This technology is coming and remember you heard it here first.  Here is some news about diesel-hybrid cars.  These are cancept cars shown in car shows, none of these are available to the public as far as I know.:

General Motors Corporation
300 Renaissance Center
P.O. Box 300
Detroit, Michigan 48265-3000
Phone: (313) 556-5000
Ford Motor Company
Customer Relationship Center
P.O. Box 6248
Dearborn, MI 48126
800-392-3673
DaimlerChrysler Corporation
Auburn Hills, MI 48326-2766
USA
Phone: 248 576 5741

Small Cars                Diesel Cars                    Hybrid Cars                   Conclusion

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