Fitting a diesel powerplant into a light-duty pickup is a practice that’s evolved from being unusual to standard.
Chevrolet’s 2020 Silverado 1500 has joined the Ram 1500 EcoDiesel, Ford F-150 and Nissan’s light-duty-ish Titan XD to provide a turbo-diesel option. Chevy’s all-new 3.0-liter Duramax turbo-diesel is an inline six-cylinder, which Nicola Menarini, director for diesel truck engine program execution, said is “one of the most refined and efficient diesel engines in the segment.”
Fuel economy is this turbo-diesel’s top selling point, and Chevy boasts the 3.0-liter Duramax propelling two-wheel-drive Silverados delivers “fuel efficiency you would expect from a family sedan.” The manufacturer reports an estimated fuel economy of 33 miles per gallon highway and 23 mpg city for 4×2 models and 23 city/29 highway for 4×4 pickups.
The 3.0-liter Duramax will also be offered on LT, RST, LTZ and High Country Silverados. It’s a $2,495 option for LTZ and High Country models, the same price as the 6.2-liter V-8 gas engine. LT and RST models get the turbo-diesel for a $3,890 increase over the 2.7-liter turbo gas powerplant. Base pricing ranges from $44,700 for an LT double cab to $56,590 for a High Country crew cab.
Compared to the gas engines powering Silverados in which the turbo-diesel is offered, the 3.0-liter Duramax is more fuel efficient. The 5.3-liter V-8’s estimated fuel economy is 17 miles per gallon city and 24 highway, and the 2.7-liter Turbo inline four-cylinder has a 20-mpg city and 23-mpg highway estimated fuel economy. The 6.2-liter (4WD) gets a rating of 16 mpg city and 20 mpg highway.
A healthy torque output is another 3.0-liter Duramax plus. The turbocharged-and-intercooled diesel generates 460 lb.-ft. of torque at 1,500 rpm (delivering 95 percent at 1,250 rpm) and 277 horsepower at 3,750 rpm. The turbo-diesel-powered 4×4 Silverado has a 9,300-pound towing capacity and 1,870-pound payload max. Chevy reports its trailering capacity “meets the needs of about 90 percent of light-duty customers,” but it’s eclipsed by the 5.3-liter and 6.2-liter gas engines with 11,600- and 13,400-pound towing capacity, respectively. The 2.7-liter Turbo’s towing max is 7,200 pounds.
Achieving top fuel economy is the result of an all-new clean-sheet-of-paper design for Chevy’s first inline-six-cylinder powering a light-duty pickup. The mission for engineers, said Menarini, was to provide “the best of diesel — outstanding fuel economy, great horsepower and responsive torque.”
Providing a solid foundation on which to create a refined and efficient engine with low noise and vibration is the “inherently balanced” inline-six configuration. The plus of an I-6 versus a dual-overhead-cam V-6 is the reduced friction afforded by the movement of only two camshafts and related valvetrains. “The I-6 configuration,” Chevy reports, “offers the perfect balance of primary and secondary forces, without the need for balancing shafts.”
Engine weight is reduced with a cast-aluminum-alloy block, and strength is added via iron cylinder liners, and forged-steel crankshaft and connecting rods. Pistons are formed with a blending of aluminum and silicon to resist heat and reduce expansion.
Active Thermal Management enhances efficiency and cold-weather warm-up, while ceramic glow plugs also help with shorter heat-up times and quicker cold starts. Active Thermal Management helps the engine to rapidly achieve and maintain optimal temperature to boost operation efficiency and cold-weather warm-up time.
Complementing the 3.0-liter Duramax’s refined character is a smooth-shifting Hydra-Matic 10-speed automatic transmission. It gains efficiency with smaller gear steps and larger ratio spread. Fuel economy is enhanced by engine stop/start technology, which shuts it off during stops and restarts when the foot is removed from the brake. This feature can be turned on or off at the driver’s discretion.
Contributing to improved fuel efficiency and acceleration with all Silverado powertrains is a 450-pound weight reduction, accomplished by using mixed materials in the body, frame and suspension. Despite being lighter, the frame gains 10 percent torsional stiffness and teams with a revised suspension featuring a softer spring rate to boost ride quality and driving dynamics.
The 3.0-liter Duramax takes advantage of the Silverado’s lighter and more-aerodynamic form, said Tim Herrick, Silverado executive chief engineer, and “utilizes state-of-the-art technologies to optimize every drop of fuel. The resulting combination offers all of the performance, refinement and capability customers want in a full-size truck.”
— Tim Spell, Motor Matters
Copyright, Motor Matters, 2019
Manufacturer Photo: Chevrolet’s all-new 3.0-liter Duramax turbo-diesel has an an estimated fuel economy for 4×2 models of 33 miles per gallon highway and 23 mpg city. The 3.0-liter Duramax, reports Chevrolet, is a “refined” turbo-diesel with low noise and vibration resulting from its “inherently balanced” inline-six configuration.