Diesel in SoCal is about 15 cents a gallon less than regular right now.
A new small truck, would have the same problem that Dakota did, fuel economy and price point. If it cannot get real separation from the 1500, it wont do well.
The other problem is small truck buyers themselves. As we have seen here at Allpar, as soon as the wish list is opened up, the factions start splitting the demand; standard cab vs. quad, vs. crew, long bed vs. short, the more you add, the closer you get to the Ram.
It's just like the hypothetical Jeep truck that Bob and I built a few years ago, you offer it one way, with few options and it pencils out.
Start making it something for everyone and you overburden the ability to produce it.