Wards drove the 2020 GMC Sierra 1500 Duramax, along with a 2020 Ford F-150 Powerstroke and 2020 Ram 1500 EcoDiesel when deciding on its 10 Best Engines and Propulsion Systems list for 2020. It was most impressed by the GM offering, with editors giving the 3.0-liter LM2 engine points for “its fuel economy and a smoothness debunking diesels’ growly image.”
The publication was particularly impressed with the Duramax 3.0-liter inline-six’s real-world fuel economy. The GMC Sierra with the LM2 engine gets an EPA-certified combined fuel economy rating of 26 mpg and Wards Auto was easily able to match this, achieving at least 24.7 mpg at all points during its testing and as much as 31.9 mpg. It says those numbers “far surpassed,” its observed fuel economy for either the Ford F-150 or the Ram 1500.
“The GM 3.0L is a great daily driver – quiet and calm, a far cry from the heavy-duty diesels that shake your molars loose,” Wards editor Tom Murphy said.
“Hard to find fault with such a smooth-running machine,” added Muprhy’s editorial colleague, Bob Gritzinger. “This, more than any other engine option, seems perfectly suited to a fullsize truck.”
Wards may have been even more impressed with the 3.0-liter Duramax diesel’s fuel economy if they tested it in a 2020 Chevrolet Silverado. The 2020 GMC Sierra 1500 diesel has an EPA certified rating of 30 mpg highway and 23 mpg city for a combined rating of 26 mpg, while the Silverado gets a rating of 33 mpg city and 23 mpg highway for a combined total of 27 mpg. As we reported previously, Sierra models typically come with more content due to their premium status, so they are tested at a higher base weight than the Silverado, giving the Chevy better fuel economy ratings.
With this recognition from Wards Auto, the 3.0-liter LM2 engine with the GM 10-speed automatic transmission has been deemed the best of the new light duty diesel powertrains. We’re sure Ford and Ram will both be hard at work trying to get more fuel economy and smoother running operation out of their smaller diesels between now and when the 2021 model year trucks are released, but for now, it seems GM is the king of the light duty diesel.
|Vehicle||Engine||Displacement||Configuration||Horsepower @ RPM||Torque @ RPM||MPG (hwy/city/combined)||MPG vs Sierra (hwy/city/combined)|
|2020 GMC Sierra 1500||Duramax Diesel LM2||3.0L||DOHC||277 @ 3750||460 @ 1500||30/23/26||-/-/-|
|2020 Chevrolet Silverado 1500||Duramax Diesel LM2||3.0L||DOHC||277 @ 3750||460 @ 1500||33/23/27||+3/-/+1|
|2020 Ram 1500||EcoDiesel||3.0L||DOHC||260 @ 3600||480 @ 1600||32/22/26||+2/-1/-|
|2020 Ford F-150||Power Stroke Diesel Lion||3.0L||DOHC||250 @ 3250||440 @ 1750||30/22/25||-/-1/-1|
Source: Wards Auto