General Motors 2.7L Turbo I4 (L3B) Engine Specs

The GM 2.7L Turbo I4 (L3B) is a 2.7-liter turbocharged inline-four petrol engine produced since 2018, developed as a modern, technologically advanced alternative to larger naturally aspirated V6 and V8 engines in GM's trucks and SUVs, used in the Chevrolet Silverado, Colorado, Tahoe, and the Cadillac CT4. It reflects GM's broader strategy of replacing larger displacement engines with smaller, turbocharged units that deliver comparable towing and hauling capability alongside improved fuel economy.

Producing between 237 and 325hp and a wide torque range of 351-583Nm depending on application and state of tune, the L3B uses a DOHC 16-valve head, a single twin-scroll turbocharger, dual direct and port fuel injection, active fuel management (cylinder deactivation), and a compression ratio of 10:1. The dual-injection system is a deliberate engineering choice to combat the carbon buildup that affects purely direct-injected engines, injecting fuel through both direct and port injectors depending on operating conditions - a more sophisticated approach than many rival turbocharged four-cylinder truck engines use.

As a relatively new engine design used in demanding truck and SUV applications, the L3B's long-term reliability track record is still developing compared with GM's much longer-established V6 and V8 truck engines, and buyers should weigh this when considering a used example, particularly one used for regular towing. The turbocharger and its associated cooling system work hard under sustained towing loads, and oil quality with strict adherence to service intervals is essential for long-term durability - more so than on a naturally aspirated engine of similar output. The active fuel management (cylinder deactivation) system adds mechanical complexity beyond a conventional four-cylinder engine and is worth having inspected if any rough running or unusual vibration is noticed. Because the L3B is still a comparatively young design, keeping up with GM's technical service bulletins and any manufacturer recalls is a sensible part of ownership, particularly for buyers using the engine for its intended towing and hauling role rather than light-duty commuting.