I just don't understand why they don't offer smaller turbo'd diesels in these big SUVs like they do in Europe. We were in Rome a few years back and an Escalade pulled up to a light and you could hear the whistle from the turbo when it accelerated and that typical diesel sound.
Most large delivery/work trucks like the Freightliner, Fiat Ducato (Think Dodge Sprinter), Mercedes, and the occasional Dodge Ram all have 1.8, 2.0, or 2.2 turbo diesels. Way better gas mileage than the 5.3 or 6.2, the same or better torque typically for towing/weight, and the turbo usually solves the acceleration problem. Especially in Italy, you have to see how much weight they put in these trucks (waiting for the shocks to pup through the mounts) and I have seen them climb those mountainous town streets effortlessly.
If it was at least an option or a typical install in your fleet vehicles like the Suburban LT which is extremely prominent in the livery market (especially on the east coast), they could reduce emissions probably by half and still meet the requirements of your typical buyers needs for towing, accelerating, etc. If I had been looking for a Burb to tow a boat or trailer I would have considered a diesel. I digress....