JIM: Reducing the weight of the vehicles is what every manufacturer is doing to get the fuel economy improved. If the weight is reduced, fuel economy and performance improve and emissions are reduced at the same time.
This weight reduction is being achieved by using aluminum and high-strength steel in more places and downsizing the vehicle when it is redesigned, such as in the new Ford Explorer.
JIMMY: One interesting take we overheard was a discussion amongst some German journalists talking about the American version of hybrids (i.e. electric with gas or plug-in electric) and how those are practically non-existent overseas. No, they use diesel engines in a lot of their vehicles and are already pulling decent MPGs. Diesel is still a dirty word here in America, with it having a stigma of being dirty. But Jim, can you explain why that’s simply not true any more?
JIM: The new diesel engines must be able to meet the same exhaust emission standards as gasoline engines. This was not an easy feat for the automotive manufacturers. Besides more electronic controls, many require the use of urea injection.
This clear, odorless liquid is injected into the exhaust system to reduce oxides of nitrogen emissions. The urea must be refilled as part of regular maintenance, which will add to the cost of ownership.
JIMMY: And why can diesel engines give so much better fuel efficiency than gasoline engines?
JIM: Diesel engines use diesel fuel, which contains more heat energy than gasoline. The higher compression and other factors make diesel engines about 20 percent more efficient than a gasoline engine.
However, a diesel engine costs more and the cost of diesel fuel is higher. Even with these factors, diesels offer surprising fuel economy and performance.
JIMMY: What I took away from the auto show was the great race to improve fuel efficiency, but it seems too many of the automakers haven’t figured out how to get the power we Americans demand (i.e. SUVs and trucks) and still get the good MPGs.
To me, especially in regards to the bigger and heavier vehicles on the market, many of which are top sellers, diesel is going to have to be the way to go. Do you agree or disagree Jim?
JIM: I agree, but the American public have not purchased the number of diesel engine vehicles compared to vehicle owners in Europe.
Several factors I think contribute to this situation, including lower gasoline prices here in the United States compared to Europe and the public remembering the older diesels that were noisy and had smelly exhausts.
However, today with clean diesels and for those who need a truck to tow a heavy load, there is nothing better than a American pickup truck equipped with a diesel engine to get the job done.
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