Cummins 6.7L Gasoline Engine in a Ram?

ShinerBock wrote:

It is not necessarily the fact that emissions systems on gas engines are figured out, it is just that the US EPA has a hard on against diesels and therefore have stricter requirements on diesels. Even though gas engines are more harmful to the environment due to their inefficiency and today's direct injected engines emit a lot of particulate matter, diesels emit a lot of NOx which is only harmful in very heavily populated areas. In les populated areas, NOx dissipates into the upper atmosphere and gets turned into a good thing since NOx is a helpful greenhouse gas which is also created by lightning, forest fires, and many other heat sources.

So, it is not that they just haven't gotten diesel emissions figured out, it is just that they keep getting stricter and stricter because the activist powers that be seem to have a disdain for them. If you look at all of our emission requirements and fuel economy test standards, they are all made to get the best possible outcome out of a gas engine, not a diesel or CNG vehicle. Although, after the SCR/DEF systems, they have been getting a lot better.

Not to get into a political discussion about which poisons are best, look at the history of pollution control on vehicles. The manufactures worked to clean the exhaust between ex valve and end of tailpipe. This caused a tremendous drop in performance and economy. My '73 Nova, (350, auto, steering brakes and air) would go about half as far on a gallon as my '72 half ton (350, auto, steering brakes and air). Bell, if drivers took the day off, and I worked my '72 F350 (360, auto ps,pb, and Holmes wrecker/body) I could come close to same MPG as the car.
But over time they have learned to clean up the combustion. Now we get much better power, better MPG, and cleaner exhaust.
At start, most pickups where used for work, not many miles so exempt. But because of the issues with emission equipment, more people started buying pickups just for transportation. This demand cause the cab to grow, and the bed to shrink to the point now most pickups look like the just forgot to put the trunk lid on. To clean the tailpipe of most passenger vehicles, had to regulate heavier and heavier trucks. Then we talk about diesels. We are in the part of evolution where we are trying to clean exhaust after made the mess is made. Performance/economy suffer, plus the failures of emission equipment reduce the dependability.