I'm not usually in this section, but as a former "industry insider" so to speak I'll tell you why it's probably not worth getting your hopes up. I worked in alternative fuels up until 2008 heading an experimental feedstock project to fuel the largest biodiesel refinery in the US. CAFE standards and RFS Act were part of my regular reading regimen. The A&F there are certainly a big part of why Jeeps will never see any reasonable fuel economy figures, but the RFS act doesn't help. There are a million loopholes in the one that essentially take the teeth out of the other (thanks, W). GM is so far under the bar right now (in real terms) because every truck they sell (and many cars) are "flex fuel" vehicles meaning they can technically run on ethanol. It doesn't cost GM anything more than a line of code, but the government treats these vehicles as if they're running on ethanol 50% of the time (yeah right, when was the last time you saw a neat ethanol pump?). That means a big truck that gets 12 miles to the gallon gets 24 as far as CAFE standards are concerned! Hybrids have a similar math when it come to calculating CAFE mileage. I don't know if there's any sort of IP that goes with the "flex fuel" scheme, but Chrysler doesn't seem to have really caught on... Or maybe someone in upper management has principles and ethics... Not sure..
You want a diesel? Cool! Me too! Why doesn't Chrysler bring diesels to the US? They keep tempting us year after freaking year with fuel economy figures, torque figures, something approaching reliability, but we won't see them any time soon. Why? The US emissions regulations are set up to effectively make it impossible for diesels to meet regulation. Why? The particulate problem in passenger cars was solved a long time ago; they're often even cleaner than gas engines in that concern. The low sulfur fuels keep the really nasty stuff out of the tailpipes. Unfortunately it's the fact that NOx is to diesels what CO2 is to gas engines. It's a much more potent greenhouse gas, so that at least has some merit. The problem is that Nitrogen bonds to the oxygen much more readily at the higher temperatures at which diesels run. A number of German manufacturers have figured out the urea after treatment trick, but Americans can't seem to wrap their heads around engines that aren't the same as every other engine (air cooled engines require a different driving style, rotary engines require additional oil, diesel engines are close but if they require urea Americans can't quite meet the curve). Mazda has figured out that an ultra-low compression ratio (on the order of 13:1) will lower combustion chamber temperatures enough to significantly reduce NOx emissions and actually meet US emissions regulations WITHOUT after treatment. I have yet to see what that does to the various attributes that make diesels worthwhile in the first place (torque, fuel economy, and reliability). The problem here is that Mazda owns that technology... Unfortunately, Chrysler messed up the Diamler partnership or they could have access to the after treatment technology... Diamler messed it up too, but hindsight is 20/20 (if the ultra awesome high tech cupholders break when Mercedes uses quality materials, of course everything is going to break when Chrysler's bean counters get a hold of it).
Unfortunately, Fiat doesn't have any cool diesel tech (they don't really have any cool tech period, it's a style brand), so no diesels here for the foreseeable future. They do have a bunch of small European city cars though! The Smart ForTwo has double digit horsepower (but doesn't follow up with the sort of fuel economy one would expect for that sacrifice) and the Scion iQ is doing pretty well on the showroom with double digit horsepower, and as I recall there's another car coming in 2013. Remember the old Volkswagens? What Chrysler is going to do (sorry Jeep guys) is bring in a few more Fiat city cars, reskin a few for the Chrysler lineup, and do their best to sell a million of them. Throw in some hybrids (I don't think either party has anything fun going on in the hybrid or electric realms, but they'll probably need to figure something out), and that's pretty much all you're going to see. Sorry to burst any bubbles.
