General Motors has reportedly cancelled development of a turbocharged six-cylinder petrol engine for its full-sized pickup trucks and SUVs as it continues to embrace V8s.
GM Authority reports word from sources familiar with the matter that the engine had been in the planning stages in mid-2022, but the company has now cancelled the program.
Rival Ford’s EcoBoost twin-turbo petrol V6 engines have become the most popular engines in the F-150 and the only engines in its full-sized SUVs, while Stellantis last year revealed a new twin-turbo inline-six called the Hurricane.
But GM has invested heavily in V8 engines, announcing a sixth generation of its small-block V8 engine earlier this year.
It will be built in Flint, Michigan, using components made in Michigan, Ohio, and New York on the back of an US$854 million (A$1.2b) investment.
The new six would reportedly have been based on the 2.7-litre L3B turbocharged four-cylinder engine currently seeing duty in the Chevrolet Silverado and Colorado and GMC Sierra and Canyon pickups, as well as the Cadillac CT4 sedan.
GM was reportedly targeting outputs of 500 hp and 500 lb-ft (373kW of power and 678Nm of torque), well over even the most powerful version of the 2.7-litre, the 242kW/515Nm tune used in the Cadillac CT4-V.
That would have been enough to shade not only GM’s current 5.3-litre V8 (265kW/519Nm), but also its 6.2-litre V8 (313kW/624Nm). The latter is the only engine offered in the local-spec Chevrolet Silverado.
With 373kW and 678Nm, the cancelled six would have also outpunched even the most powerful six-cylinder F-150, the 336kW/691kW Raptor, and would have locked horns with what’s currently the most powerful iteration of Stellantis’ Hurricane six.
The Jeep Grand Wagoneer L produces 380kW and 678Nm.
It wouldn’t have been the first twin-turbo petrol six to join GM’s engine line-up. The company currently offers a 3.0-litre twin-turbo V6 in the Cadillac CT5 and CT5-V and a 3.6-litre twin-turbo V6 in its Cadillac CT4-V Blackwing.
The latter vehicle is the most powerful, pumping out 352kW and 603Nm.
GM used to offer a base naturally aspirated 4.3-litre V6 in the Chevrolet Silverado and GMC Sierra pickups, but recently discontinued it. Instead, the pickup trucks’ ranges open with the turbocharged 2.7-litre four.
That’s unusual for the segment, as none of these pickups’ rivals offer four-cylinder power. The F-150 and Ram 1500 ranges, for example, open with atmo V6s.
GM does continue to offer a 3.0-litre turbo-diesel inline-six in not only its full-sized pickups, but also its Chevrolet Tahoe and Suburban, GMC Yukon and Yukon XL, and Cadillac Escalade SUVs.
With the Ram 1500 and Ford F-150 recently losing their turbo-diesel sixes, this makes the GM offerings outliers in the North American market.
Move up to heavy-duty pickup trucks like the Ford Super Duty, however, and turbo-diesels become more common.
GM’s profitable full-sized pickups and SUVs are helping pay the bills for the company’s rollout of electric vehicles, including full-sized electric pickups like the Chevrolet Silverado EV and GMC Sierra EV.
The company plans to only sell electric vehicles after 2035.
GM will offer 30 electric vehicles globally by 2025, with 40 per cent of its US line-up to be all-electric by the same time.