GM 6.6 Liter V-8 L8T Engine
The L8T V8 is a gasoline engine produced by General Motors for use in Heavy Duty pickup trucks. The engine displaces 6.6 liters in a V8 configuration and an OverHead Valve (OHV) layout otherwise referred to as push-rod.
The 6.6L V8 L8T is built on a cast-iron Small Block, enabling it to have long-term durability. Thanks to aluminum heads and direct injection, the engine delivers more precise fuel control resulting in a higher compression ratio of 10.8:1. That enables a power output of 401 horsepower and 464 pound-feet of torque (in the 2020 Silverado HD and 2020 Sierra HD), with strong performance at low rpm, where it is needed when pulling away with a loaded cargo box or trailer.
The L8T also features a forged steel crankshaft, forged powder-metal connecting rods and additional high-strength components to provide the added strength and durability demanded by Heavy Duty truck customers.
The L8T replaces the 6.0L V8 L96 / LC8 engine and makes over 11 percent more horsepower and over 21 percent more torque.
|GM RPO Code:||L8T|
|Type:||6.6L V-8 gasoline|
|Bore & Stroke (in / mm):||4.06 x 3.86 / 103.25 x 98|
|Block Material:||Cast iron with nodular iron main caps|
|Cylinder Head Material:||Cast aluminum|
|Valvetrain:||Overhead-valve, two valves per cylinder, variable valve timing|
|Fuel Delivery:||Direct fuel injection|
|Recommend Fuel:||87 octane|
|Power (hp / kW @ rpm):||401 / 299 @ 5200 (SAE certified)|
|Torque (lb.-ft. / Nm @ rpm):||464 / 629 @ 4000 (SAE certified)|
|Predecessor:||6.0L V8 L96/LC8|
|Manufacturer||Model Year||Make||Model||Transmission||Power (hp / kW) @ RPM||Torque (lb-ft / Nm) @ RPM|
|General Motors Company||2020||Chevrolet||Silverado HD||6-speed auto (6L90)||401 / 299 @ 5200 (SAE certified)||464 / 629 @ 4000 (SAE certified)|
|General Motors Company||2020||GMC||Sierra HD||6-speed auto (6L90)||401 / 299 @ 5200 (SAE certified)||464 / 629 @ 4000 (SAE certified)|
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