Sources suggest it will be based on the four-cylinder Global Medium Engine used in the Jeep Wrangler JL and Alfa Romeo Giulia.
Inline six-cylinder engines haven't been used in FCA vehicles since the Jeep Wrangler JK generation debuted in 2007, but a report by Allpar suggests the automaker is working on a new straight-six engine to eventually replace the ageing Pentastar V6.
According to the publication, the original plan was to use boosted versions of the Pentastar V6 but this proved to be impractical. Instead, Allpar's "reliable sources" suggest FCA will base its new straight-six around its new four-cylinder Global Medium Engine used in the Jeep Wrangler JL and Alfa Romeo Giulia, which should be smoother and more compact than the current Pentastar V6 unit, as well as being easier to produce alongside the four-cylinder units.
FCA may not even need to change the architecture of the engine, and instead simply add two more cylinders. Allpar's sources go on to suggest that its displacement could be pegged at 2.99-liters to avoid taxes applied to engines that have more than 3.0-liters in some European countries. There are even murmurs that Ferrari will use the same core architecture to work on a new engine for its cars as well as Maserati models.
The engine would be built in several guises including SRT-badged performance models, while production will reportedly take place at one of FCA's plants in Dundee, Michigan, as well as a facility in Trenton, Michigan. Rumors that FCA is working on a new straight-six engine have been circulating for years now, but it's best to take them with a grain of salt until we get official confirmation from FCA.