So who does that leave? Well, ideally, it would be a company that does not already have a significant US presence, and does not have a large truck and SUV line already in their product mix. To such a company, a merger or acquisition might make sense. They would gain entry into the pickup truck and SUV market instantly, without having to spend years of R&D money developing their own lines - and product reputation.
Volkswagen. That might be the ticket. They want to be the world's largest car maker, and are doing so, squeaking by Toyota and GM to claim the prize - in spite of dieselgate. They don't have much of a US presence in terms of manufacturing (one plant only, recently opened) and have little or nothing in the way of trucks and SUVs to sell. They already have sold some Chrysler products in the past - rebadging the Dodge Caravan as the "Routan" for a few years. It could be a good match for VW, expanding their US manufacturing base and dealer base. Their expertise in car-making could fill in the gaps in the Chrysler lineup (which as noted, is shy on cars) while at the same time providing them with a line of hot-selling SUVs and trucks.