The Last Diesel Standing: The Chevy Silverado 1500
American truck buyers have a seemingly insatiable appetite for power and capability. However, many also want to be economical at the pump. As diesel engines become less common globally, enthusiasts can still find solace in full-size pickup trucks. While the Big Three automakers in the United States offer massive diesel trucks, only one manufacturer still produces a half-ton truck with a diesel engine: the Chevrolet Silverado 1500. Interestingly, you can get it with a diesel engine for around the average price of a new car. This makes it an attractive option for those seeking diesel efficiency in a modern truck.
The diesel engine experienced a resurgence in America during the late 2000s and early 2010s. Volkswagen and Mercedes-Benz played key roles in changing American consumers’ perceptions of diesel power.
Over a couple of decades, these automakers carved out a niche market that grew to have significant mainstream appeal. The diesels of the late 2000s weren’t like the smoky, noisy, and underpowered engines of the 1970s. Modern diesel engines are quieter, smoother, and much quicker. They also delivered excellent fuel economy, often surpassing that of comparable gasoline engines and hybrids, without the downsides of older diesel technology. These engines were built to last. You should be able to find early 2000s Volkswagen diesels with hundreds of thousands of miles and pickup trucks with even more.
GM’s Entry and Diesel’s Decline
In the 2010s, General Motors also entered the diesel market with the Chevy Cruze diesel in 2014. In the years following the 2015 Dieselgate emissions scandal, GM capitalized on the opportunity to gain market share as Volkswagen pulled out of the diesel market. GM didn’t see diesel as the problem, rather, they felt Volkswagen had ruined diesel’s image. This led to the launch of diesel crossovers, but also the Chevy Colorado and GMC Canyon diesels in 2016. These mid-size trucks were the only diesels in their class. Ford did not offer a diesel in the new Ranger, Ram doesn’t sell a mid-size truck in America, and import brands had no entries in this segment either.
What America did see was a run of compact diesel engines in half-ton pickups, each of the Big Three offering their versions. Of those, only the Chevy Silverado 1500, with a 3.0-liter Duramax engine, remains. As of this writing, it’s also the cheapest entry point into a new diesel truck in America.
GM’s Diesel Dominance and the Duramax
In the past, General Motors led the diesel market in the United States. GM subsidiaries’ diesel engines powered various aspects of American life. For decades, if you rode a train pulled by a diesel-electric locomotive, the locomotive was likely built by the former GM Electro-Motive Division. Other EMD-built and powered locomotives hauled goods across America.
GM’s former diesel dominance ran deep. Detroit Diesel produced one of the most popular highway semi-tractor engines, the Series 60. It was also involved in power generation and marine industries. General Motors was so powerful that it dominated the intercity and transit bus industries. A person could take a train pulled by a GM product, ride a GM-produced bus, and then buy a GM car.
General Motors has since reduced the scale of its transportation operations, selling off the EMD and Detroit Diesel operations as well as ceasing production of highway tractors and buses.
GM’s Diesel Pickup Innovations
While GM was a pioneer in diesel technology for most of the 20th century, it was late to develop the ideal formula for diesel pickup trucks. In the 1980s, Ford and Dodge gained ground by mounting large diesel engines to their trucks, providing both power and fuel economy. GM’s response came in 1992 with the 6.5-liter Detroit Diesel V8. It was followed in 1997 by the 6.6-liter Duramax LB7. With a common rail, direct-injection engine that produced 300 horsepower and 520 lb-ft of torque, it surpassed Ford and Dodge’s offerings. The Duramax V8 became a mainstay of GM’s diesel trucks.
The Babymax: The 3.0-liter Duramax
The 3.0-liter Duramax in the Silverado 1500 is a straight-six. GM’s plan to regain diesel dominance after Dieselgate included introducing diesel engines into the Chevy Colorado, Chevy Express, Silverado 1500, Tahoe, and Suburban. Before the 2025 model year, you could also buy a Cadillac Escalade 600D, which featured a smooth diesel engine.
The Torino group in Italy developed the 3.0-liter Duramax. This technical center was responsible for reducing engine fuel consumption across the GM portfolio. [Ed Note: Italy has for decades been a dominant force in Diesel development, with the famous VM Motori having built diesels for Chrysler/Jeep/Dodge/Ram, Land Rover, Alfa Romeo, and many more -DT]. The Torino facility also developed the Opel 1.6-liter “Whisper Diesel” engine found in the Cruze, Equinox, and Terrain vehicles. The facility was an important part of GM’s internal combustion development. In 2020 the facility was sold.
The Technology Behind the Babymax
The 3.0-liter LM2 Duramax straight-six came from Torino. It was built on a scalable architecture with models from as small as 1.5-liter three-cylinder engines. A chain connects the crankshaft to the high-pressure fuel pump. Another chain connects the fuel pump to the camshafts. Also connected and moving down from the crank is a wet belt that drives the oil pump. Wet belts are timing belts constantly immersed in engine oil.
Engineer John Barta explains that the oil pump has a variable displacement, putting out only the amount of required oil. This prevents waste and offers improved efficiency. The wet timing belt is also designed to reduce wear and noise, improving efficiency and providing fuel savings of around 1%.
The fuel system delivers fuel at a maximum injection pressure of 36,500 PSI. Fuel is delivered by a twin-piston pump and rides the common rail before being fired through injectors. The solenoid injectors are Denso G3.5S units and designed for up to 10 injections per combustion cycle. The engine design minimizes noise and lowers emissions. The engine has aluminum heads, a thin steel cylinder, and seven main bearings for the crankshaft. The combustion processes were among the driving theories. The cylinder head is flat, and the bowl-shaped pistons have zero relief cuts for the valves. Simulation and single-cylinder engine studies showed that vertical valves optimize the swirl.
The ceramic glow plugs allow the engine to start at -22 degrees Fahrenheit without a block heater. The engine development and engineering, as well as primary calibration, took place in Turin, Italy. Barta further notes that the engine’s design allows for a 15:1 compression ratio, which is good for lowering emissions. A variable geometry turbo allows for prompt power. With the LM2 Duramax the electronic actuator and snail provide 29 pounds of boost. Further aiding the engine is a charge air cooler and short piping, allowing fast spooling. At launch, the LM2 Duramax was rated at 277 HP and 460 lb-ft of torque.
Other technologies include swirl valves in the intake runners to help emissions and a rotary valve to control coolant flow for better heating and cooling distribution. The ceramic glow plugs help the engine start at -22 degrees Fahrenheit.
Performance and Pricing
General Motors launched the Babymax in its light-duty trucks for the 2020 model year, offering another half-ton diesel option alongside the Ram 1500 EcoDiesel and the F-150 Power Stroke. It was the firm’s first half-ton diesel since 1997.
The 3.0-liter diesel achieves up to 29 mpg on the highway in two-wheel-drive trucks and 22 mpg in the off-road ZR2 model. Car and Driver noted that the diesel ZR2 gets 6 mpg more than the 6.2-liter V8 gasoline model.
In 2020, a Silverado 1500 with the Babymax cost about the same as a truck with the 6.2-liter V8; however, towing capacity was less. Fortunately, GM has resolved this, and the Babymax now tows up to 13,300 pounds, close to the 6.2-liter V8 option. The EPA rates the current engine as high as 23 mpg city and 29 mpg highway in certain two-wheel-drive trucks.
For a 2025 Chevrolet Silverado LT with a double cab, a standard bed, and two-wheel-drive, the price is around $51,145 including the diesel engine and destination fees.
The cheapest new diesel truck on the market is not much more than the average price of a new car. If you need diesel power, want to spend the least amount of money, and only need a half-ton truck, the Chevy Silverado 1500 with the 3.0-liter Duramax is your only choice.
