A few year ago, the same people claimed that it would be impossible to produce cleaner running diesel without going out of business. Of course, they were wrong. Without their ongoing resistance, cleaner running diesels would have been around 20/30 years ago. Regulations were required to force the issue.

Tar sands extraction and shale gas people have the same attitude and they will keep on polluting as long as we let them to it.

You both could not be more incorrect or misinformed. Cummins was a driving force for responsible regulation for decades. They admitted (in the 1960s) that their products we part of the nation's air pollution problems and vowed (through helping the EPA draft regulations) to improve. That's what has led to its success...being able to meet emissions regulations while also meeting their customer's expectations. Read your history, don't just assume.

The same assumptions have led people to deride the American auto manufacturers as "holding back progress," when in fact it is the consuming public that has not demanded (until, recently, and begrudgingly) progress on these fronts...

And if you let regulators (pushed by power happy Californian senators) set the standards, you end up with cars that need marginally less gas than before but no regular consumer could afford. Now, if that extra cost went to the domestic manufacturers rather than the not-so-friendly oil-rich countries, so be it. But the Walmart model dictates that in order to bring costs back down, production moves to a place where we've already sent too much money and too many jobs.

If heavy duty and industrial engine and vehicle manufacturers are forced by these same regulators to produce products that must meet impractical, then you will either have shippers continue on with older, more polluting vehicles, or buying new and pass on the cost to consumers.

Either way, there will be a price to pay. Either in technology or in health/security. It's really up to the public (not 5% of their elected officials) to decide how they want to pay the costs. Maybe those elected officials should spend more time educating and less time dictating. (as a footnote, I support increasing efficiency across the board, but I don't support (incorrectly) blaming one small part of the spectrum)

I agree with John. I would go even further to conclude that misinformation is the middle name of HarveyD.

There is a big difference with CAFE regulations for passenger cars and emission norms for heavy-duty vehicles. Experience from Europe, Japan, etc. tells us that a car can use significantly less fuel than the current US CAFE norms. On the contrary, technology for reducing NOx emissions to the US 2010/EU 2013 level has not been available until now. For particulate emissions, I would say that the DPF technology might have been introduced somewhat earlier if the legislators would have provided for better long-term planning in the development of regulations. Still, the problems seen in the field with DPFs on some US 2007 engines indicate that the technology might not have been fully mature then. I do not expect durability problems with SCR to meet US 2010, since this technology - promoted by the engine manufacturers - has already been used for a couple of years in Europe. US EPA was not in favor of this technology. If EPA would have won this debate in the USA, there would not have been any US 2010 engines today. Industry persisted and now we have US 2010-compliant engines. So, who were the bad guys in this case? Another example: In Europe, car and engine manufacturers have participated actively in the development of measurement methods and legislation for particle number emissions. This has given EU the toughest particle emission standards in the world. I doubt that the EU legislators alone could have accomplished this.

Another factor to consider is fuel quality. For long, USA was the market with the toughest emissions standards and the “poorest” diesel fuel quality. The new emission control technology simply requires better fuel. It is not possible to introduce this technology before the fuel is available. For example, we would have had no three-way catalyst without unleaded fuel. Refineries also must be given some time to adapt, so nothing can happen overnight. The sulphur level in US diesel fuel has now been reduced to almost the same level as in EU but there are still several other fuel parameters that could be improved if health concern was of interest.

Finally: Does anyone remember the CARB regulation to enforce ZEVs in the 1990´s? How clever was that? And now history might repeat itself with the new proposals by CARB...