GM Fits Sixth-Generation Small Block V8s to 2027 Silverado and Sierra

General Motors has revealed two new V8 engines for its 2027 full-size pickups, the Chevrolet Silverado and GMC Sierra. The units displace 5.7 litres and 6.6 litres, forming the sixth generation of GM’s Small Block family. The move underlines how central conventional internal combustion remains to the company’s truck strategy, even as electrified options multiply across the segment.

By rolling out fresh displacement figures rather than leaning on its existing lineup, GM is signalling that buyers of heavy-duty and full-size trucks still prioritise torque, towing capability and proven architecture over battery-electric alternatives. The two engines slot into a market where rivals continue to hedge between combustion and electrification.

The announcement lands as a pointed reminder of the segment’s dynamics: before any electric powertrain can claim dominance in American trucks, the incumbent V8 still sets the benchmark. GM has not yet detailed output figures, fuel economy or availability beyond the 2027 model year timing.