NHTSA Fuel Economy Proposal
The size of each model is based on its “footprint”, that is the track width multiplied by the wheelbase, and that the smaller this area is the higher the fuel economy (MPG) of the vehicle must be. It is intended that this would raise the average fleet fuel economy.
I also believe this is NHTSA’s solution to their dilemma of how to categorize a vehicle as a passenger car or a light truck, a dilemma that has become markedly more of an issue with so many different models now available from manufacturers.
However, this proposed regulation potentially won’t achieve its objective because manufacturers will build larger, less efficient models than they could since they have lower fuel economy hurdles to clear, relative to smaller vehicles. It’s a disincentive for manufacturers to offer smaller (and presumably more efficient) vehicles.
If that is the case then the way to have a more efficient vehicle fleet is to leave it to the market to demand more efficient vehicles by voting with its money. So why have the burden of this additional change?
Every manufacturer should be accountable to one standard, and not have their thresholds based on their product mix. Foundations should be built on level ground. NHTSA should clarify the definitions of automobiles and light trucks, and apply these definitions to all vehicle manufacturers the same way.
Here’s a link to the proposal (scroll down to National Highway Traffic Safety Administration):