Hello, I'm new to this forum. I have been posting on Mopar Insiders for a number of months, but the electrified Ram talk here has prompted me to respond.
For me, it is natural to assume that an electrified Ram pickup would be a 1500. After all that is what the previously built PHEV Rams were. Also leading to this assumption is the fact of all the electric pickups proposals the media talks about are targeting the consumer market. Fleet and commercial trucks are more mundane. (Perhaps the battery electric F-150 is an exception.) Much of the details concerning the Jeep Wrangler PHEV drivetrain have been revealed, so we know it will use a P2 hybrid version of the ZF 8-speed automatic. The conventional versions of this transmission are in use already in Ram trucks, so it is obvious that the hybrid setup would fit in the Ram 1500. I don't know what internal combustion engine a potential next generation Ram 1500 PHEV would use. The Wrangler 4Xe uses the GME four, while the Pacifica hybrid uses a Pentastar V6. The Aspen/Durango/Ram hybrids of the past had 5.7 Hemis.
As far as a fully battery electric pickup is concerned, I have to wonder if FCA would want to pursue that. BEV vans from Fiat will soon be under production and this is what most of the customers buying commercial vehicles want. A battery-electric pickup truck requires a huge financial commitment, while a plugin hybrid system borrows from previous commitments. Those parts being the ZF transmission, electronics, programming, and tooling. Much of this is either in place for the Wrangler or underway for the larger Wagoneer. A plugin hybrid solves range anxiety problems while allowing the same vehicle to operate in zero emissions zones. Low and zero emission zones aren't only found in Europe. That are also being established for municipal vehicles in a few US cities. The implications for potential fleet sales are obvious.
Which leads to my next point.
Is there a HD Ram hybrid in the future? The evidence is strictly circumstantial, but such a vehicle remains a possibility. The earlier plugin hybrid project using Ram 1500 pickups, with some Chrysler and Dodge minivans was a cooperative effort between the US Department of Energy and whatever the Chrysler company called itself in those years. (I think it was around 2012-15.) The details of the program can be found here,
https://www.energy.gov/eere/vehicles/vehicle-technologies-annual-merit-review
I'm sorry you are going to have to dig around for the details of the Chrysler PHEV project, but it is in there. One of the results of that program has been the Pacifica hybrid.
One of current programs the DOE has going is called the "medium-duty-urban-range-extended-connected-powertrain", or MURECP. Bosch is currently involved in a project through their automotive division. It is a Class4 Delivery van PHEV. The project is at the development stage. the details may be found here,
https://www.energy.gov/eere/vehicles/downloads/medium-duty-urban-range-extended-connected-powertrain
FCA is not directly involved in this project, but the delivery van does use a 3 liter EcoDiesel V6 along with the ZF 8-speed automatic. The key to Bosch's hybrid setup is a dual-planetary gear transmission (e2PG), or as they also call it the "e2PG powersplit/multi-mode transmission." The operation of this drivetrain is similar to the Chevy Volt. One of the lead engineers for the Volt program is Micky Bly, who currently has a cubicle in Auburn Hills. Chevrolet called the Volt a range extended electric vehicle(REEV), and Bosch uses the same description for the project.
Bosch supplied the drivetrain for the Fiat 500e California compliance car. While that program was limited production money pit, Bosch intends their REEV system as an optional component for medium duty trucks, such as the Ram 4500 and 5500 trucks. It would probably fit in a 3500. BTW, they are claiming a 60 mile battery electric range, more than enough for zero emission zones.