Ram made worldwide headlines in early November 2023 when it announced its 2025 1500 trucks would offer a turbocharged gasoline I6, EV powertrain, and even an EV with a gasoline range extender generator. But the entire show may be a redirection to hide the automaker’s real intention: an all-new diesel powerplant. Alright, the new lineup is more than a distraction. But Ram is definitely also engineering one or more new diesel engines.

The 2025 Ram 1500 changes everything

First of all, the big news. Ram is tossing its 5.7-liter Hemi V8. The 2025 Ram 1500’s entry-level engine will still be the 3.6-liter Pentastar V6, while its premium option will be the twin-turbocharged 3.0-liter “Hurricane” I6. This engine will come in a regular tune (420 horsepower/469 lb-ft) or a “high output” version (540 horsepower/521 lb-ft). In an unexpected twist, this 2025 Ram 1500 will make more horsepower than any Ram 2500.

If that isn’t enough ponies for you, you can also opt for the AWD, two-motor EV version: the Ram 1500 REV. The Ram REV will make 663 horsepower and 615 lb-ft of torque, tow 14,000 pounds, and rocket to 60 mph in 4.4 seconds. For some reason, the phrase “supertruck” comes to mind.

I know what you are saying: that’s useless in the real world, towing can slice an electric truck’s range in half! Ram has you covered there, too. The cleverly named “Ramcharger” version of the electric truck has a Pentastar V6 engine under the hood–but not to drive the wheels–to charge up the battery on long trips. It’s technically a hybrid, but is unlike any other truck on the road.

These three powertrains give Ram truck fans a lot to think about. So maybe that’s why the automaker didn’t even bother mentioning the all-new diesel powerplants in the works.

Does Ram offer a diesel engine?

You can get a heavy-duty Ram truck (2500+) with Cummins’ 6.7-liter turbodiesel. Ram also offered an EcoDiesel V6 in the 1500, which got up to 33 mpg on the highway. It canceled this engine earlier in 2023. The reason may have been an all-new diesel powerplant.

Ram does not have the same research and development budget as General Motors or Ford. So it may not surprise you that Ram Trucks has never developed its own in-house diesel engine.

By 1989, both Ford and GM offered powerful yet efficient diesel engines in their heavy-duty trucks. To catch up, Ram turned to Cummins, which offered its industrial-grade 6BT turbodiesel I6. Cummins-powered Rams have a cult-like following to this day.

In 2009, Fiat and Chrysler Corporation companies combined engineering prowess to develop several engines, including the 3.0-liter “EcoDiesel” V6. It introduced this engine in the 2014 Ram 1500. But after three generations, the EcoDiesel is officially dead.

In 2021, Fiat Chrysler Automobiles joined Peugeot Group (PSA) to form Stellantis. This 15-brand conglomerate may be consolidating its engine lineup, but it is far from done with internal combustion. In fact, Stellantis is engineering two all-new diesels.

Will Ram trucks get a new diesel engine?

We know Stellantis–Ram’s parent company–is working on two new diesels, both a low and a high-displacement engine. The larger engine will almost certainly end up in a Ram truck. But the smaller one may be the next range-extender generator for Ram EVs.

Micky Bly is Stellantis’ head of global propulsion systems. According to Automotive News, he admits that when FCA and Peugeot merged, they had too many separate engines to be sustainable. In fact, PSA builds over two million diesel engines annually, making it the global diesel leader.

Bly said, “We are aggressively streamlining our diesel portfolio. We already exited the 3.0-liter diesel. We will have a low-displacement diesel and a big diesel that’s coming in the future.”

If Stellantis is serious about consolidating its engine offerings, there’s a good chance it engineers diesels with the same footprint as its gasoline I4 and I6. Obviously, these engines will need different heads and internals. But in a future engine generation, they could theoretically even share blocks and thus displacements.

These new engines will likely leverage PSA’s advanced diesel technology. The high displacement one will almost certainly find a home in Stellantis’ shared full-frame chassis (the STLA-Full architecture), which underpins the Ram truck. Will the new large-displacement diesel go in the Ram 1500? Or will it be a Cummins replacement for the heavy-duty Ram trucks? We’ll have to wait and see.

So what about Stellantis’ smaller new diesel? It will almost certainly be for smaller vehicles, such as the efficient diesel-powered compacts Peugeot and Fiat already sell in Europe. But it might have another use here in North America.

While the 2025 Ram 1500 features the all-new Hurricane I6, it will also come with the much older Pentastar V6 (which is about to turn 15 years old). It seems that the automaker had enough bandwidth to engineer and test a new top-trim engine but is putting off a new base engine until the sixth-generation redesign. There’s a very good chance this engine will be the next-generation turbocharged I4. Like the Pentastar, this engine may end up powering entry-level trucks, as well as becoming the range-extender generator in its next Ramcharger.

Why is Stellantis taking the time to build another generation of internal combustion engines? Because much of the world does not yet have the infrastructure to support EV-only transportation. Bly said, “ICE is here to stay for a period of time. We are growing capacity, adding capacity, for South America, the Middle East and Asia Pacific.” What Bly did not say is that large swaths of the USA do not yet have the public charger network to support EV-only lifestyles. But while Stellantis plans on offering 100% EVs in Europe by 2030, in its North American plan that number is just 50%.

Next, read about the cheapest diesel pickup truck of 2024, or see the 2025 Ram 1500 reveal for yourself in the video below: