It seems the Diesel Revolution is over, Nissan Today just announced that they are discontinuing the Cummins Diesel in their Titan pickup citing very poor sales.
And one can thank the emissions stuff that has inflated the cost of buying a diesel. A diesel is complex enough with fuel issues over and above what gasoline has. The motor has to be built with better components. To make the engine eat its own feces, having to water cool that before it goes into the intake, and the soot loading it does to an engine really makes a modern diesel not worth the trouble to many folks. And I haven't even mentioned SCR/DEF and DPF issues. Having diesel fuel gel or ice up in cold weather and being sidelined on a highway in the middle of the night at -10F is not fun for anyone, especially those who are not diesel savvy and know one should always carry proper tools, fuel filters, diesel fuel additives, etc.
I deal with all these things for my commercial stuff. I can change a fuel filter along side the road in just a few minutes and be ready to roll again. I deal with it every winter. It is harder to do that on diesel cars and pickups usually than it is on heavy commercial trucks. And even though I have many decades of experience with diesels and purchase about 21,000 gallons of diesel fuel a year for my business stuff, I have no desire for diesel in my personal pickup and car. In days gone by, maybe. With today's diesels, no way. It takes a very special need to get me to even consider diesel nowadays.
And if we back up several years ago when diesel was fondling with $5 a gallon, one could barely give a diesel powered vehicle away. And it could always happen again. Many folks remember that and don't want the risk.
It is sad that the OEM's didn't offer up competent diesels in smaller vehicles back in the 90's when it was more viable and the public could have become more diesel savvy early on. They drug their feet too long and wasted a lot of R&D. They are doing it again with not investing in better performing engines that take up half the space of a typical V or inline engine, use 50% fewer parts, has a lower stance in an engine compartment, and deliver better fuel economy.
GM had a developer doing just that right under their nose in Detroit. That developer ended up selling the tech to Chinese concerns. Check out the OPOC (opposed piston opposed cylinder) engine. It was modular and the engine size could be doubled by just adding another module. No extra tech involved. Was designed in such a way that it could use diesel, gasoline, propane, NG, ethanol with very little modification. Used electric driven supercharging. No valves, cams, or overhead crap on traditional engines. And the modules could be disengaged from each other during low power times and reengaged as needed without creating drag on the rest of the motor. A 8 piston engine would take up no more space longitudinally than a 4 cylinder inline engine.