Chevrolet Silverado HD’s eye-watering 8.3-litre V8 detailed
General Motors has unveiled the new ‘Mongoose’ 8.3-litre turbo-diesel V8 for its heavy-duty pickups, leaving the current 6.6-litre Duramax in the dust.
The world’s largest V8 engine in a road-legal production vehicle is here, with General Motors lifting the lid on its new 8.3-litre turbo-diesel V8.
Codenamed the ‘Mongoose’ – a predator to the scorpion, which is Ford’s name for its 6.7-litre Power Stroke turbo-diesel V8 – the new V8 engine will replace the 6.6-litre Duramax found in the Chevrolet Silverado HD and GMC Sierra HD in North America.
Its 8.3-litre (or 507 cubic-inch in the old money) displacement makes it 25 per cent larger than the 6.6-litre V8 it succeeds, while also being far bigger than the 6.7-litre engines in its Ford (V8) and Ram (Cummins straight-six) rivals.
That larger displacement has unlocked greater outputs, with the 8.3-litre turbo-diesel V8 capable of producing up to 414kW and 1668Nm, delivered to all four wheels through an Allison 10-speed automatic transmission.
For context, the 6.6-litre Duramax makes 350kW and 1332Nm in Australia, the Ram 2500/3500’s 6.7-litre Cummins straight-six produces 313kW and 1458Nm, and the Ford Power Stroke V8 develops 373kW and 1627Nm.
According to GM, the new engine is a complete clean-sheet design, becoming the first heavy-duty V8 designed, developed and manufactured in-house by the carmaker.
Notable improvements include a compacted graphite iron cylinder block and fully forged crankshaft, connecting rods and steel pistons, as well as a dual-stage air-to-water charge cooling system.
“This new diesel engine is the culmination of decades of GM diesel development and integration,” said GM’s Executive Chief Engineer for Global Engine and Battery Systems, Norman Peralta.
“From the clean-sheet architecture and combustion system to the cooling, aftertreatment and transmission calibration, this is a powertrain built with heavy duty purpose and pride.”
Other enhancements have been made to the Silverado HD and its GMC sibling alongside the upgraded engine, such as a stronger electric power steering system (delivering up to 30 per cent more assistance), larger front brake rotors (up from 355mm to 371mm), plus electronic braking for the first time.
In the US, the Silverado HD can tow up to 17,200kg with a gooseneck hitch, or more than 9070mm with the largest available tow ball.
Chevrolet’s Australian division is yet to announce if the updated Silverado HD will come to local showrooms. Locally the Silverado HD has consistently outsold its Ram 2500 and 3500 rivals over the past handful of years.
