Do Hybrid Diesel Cars Exist?

Hybrid vehicles are more common than ever before, with virtually all mainstream automakers in the U.S. offering a hybrid in their lineups. Most of the hybrid vehicles we see today utilize electric motors in conjunction with gasoline engines, while only a handful can be found with diesel powertrains. It's a wonder why there aren't more diesel hybrids, given the already great fuel efficiency and torque of diesel engines is a great combination alongside the low-speed efficiency and emissions benefits of electric assistance. Whilst diesel hybrids do exist, they are not available for the U.S. market.

Diesel hybrids have, however, found success in European markets. One of the best examples in recent years being the Mercedes-Benz GLE350de, a plug-in hybrid luxury SUV that merges electric power with a 2.0-liter four-cylinder diesel engine. Mercedes has several other cars with a diesel hybrid power unit, with manufacturers like Audi, Volvo, and Range Rover also offering vehicles in the same class. While these vehicles have great fuel efficiency and low CO2 emissions, they have struggled to gain traction in automotive markets globally.

Although they are not available in the states, diesel hybrids do exist, but they are not nearly as popular as their gasoline counterparts. Despite the theoretical efficiency advantages they pose, there are specific reasons as to why they haven't caught on like petrol hybrids have.

As mentioned above, diesel hybrids make a lot of sense on paper. When you compare diesel engines with gasoline engines, diesels are more fuel efficient, often more durable and reliable, and cheaper to run. Adding an electric motor to handle low-speed driving — where diesel engines are less efficient and produce more emissions — could create an ideal drivetrain for both urban and long-distance driving. Yet, the reality hasn't matched the potential.

One key reason is cost. Due to their higher compression ratios and need for stronger parts, diesel engines are more expensive to manufacture. Throwing in hybrid systems to the mix, especially plug-in versions, only adds to the cost and complexity of the engine. This combination leads to a price increase that may be hard to justify, given that gasoline hybrids can already deliver exceptional efficiency at a lower entry price.

Emissions compliance is another obstacle. Whilst diesel engines produce lower CO2 emissions, they release more nitrogen oxides and particulate matter than gasoline engines do — this makes gasoline hybrids the obvious choice given the ever-tightening global emissions standards. The Volkswagen Dieselgate scandal is another contributing factor to the move away from diesel powertrains entirely, even in Europe, where diesel engines used to be far more prevalent.

So, do diesel hybrids have a place in the U.S. market in 2025? There are currently no new diesel hybrid vehicles available to American customers, and nothing suggests that manufacturers have any interest in bringing them stateside. High manufacturing costs, low consumer demand, and issues around emission regulations, means the market just isn't there.

In contrast, diesel hybrids still have a small presence in Europe, especially among plug-in hybrid SUVs like the Mercedes GLE350de and its sleeker sibling, the E300de estate. These vehicles appeal to buyers who want long highway range with the added benefit of local zero-emissions travel. But with the growing dominance of EVs and stringent emissions laws altering car design, it's possible that diesel hybrids may soon become obsolete over the next decade.

Diesel hybrids continue to make more sense in commercial applications, such as transit buses or delivery fleets, where their torque and efficiency deliver measurable gains. But for consumers — especially in the U.S. — the future is clearly leaning toward simpler gasoline hybrids or fully electric powertrains.