Today, GMC and Chevrolet remain closely aligned on the engineering side of things when it comes to trucks. We may see more of that change with the 2019 Chevrolet Silverado and 2019 GMC Sierra, but decades ago, things were different.
Back in the early 1960s, GMC wanted something monstrous to plop under the hoods of semi trucks, so engineers built an 11.5-liter V12 engine, Driving reported. It’s real, and it provided real big torque numbers for the day. At 2,100 rpm, drivers had access to the massive V12 engine’s 625 pound-feet of torque, though power was rated at just 275 hp. Still, it was a beast.
Amid inexpensive gasoline prices, heavy-duty and semi trucks often utilized gas-powered engines over diesel, which led to the gasoline-fed V12’s birth. GMC didn’t just slap two V6 engines together, however. The brand built a unique block, cam, a special oil pan, and the special crankshaft weighed 181 pounds alone. Total weight of the engine? A portly 1,500 pounds.
The engine never found its way into regular trucks from GMC or Chevrolet, but a Florida-based shop will gladly sell buyers a rebuilt unit. GMC produced only about 5,000 V12 engines between 1960 and 1965, which makes this a pretty special engine.