In the Museum Of Obvious Labels, the General Motors Sidewinder must take centre stage. After all, military around the world are famous for labeling missiles, guns, tanks…anything they're able to spray paint a few symbols onto. The Sidewinder says, simply, "TEST BED" on its front and rear, with what looks like an aluminum box in the first photo labeled "CARGO".
Cool, nice work. Great labels.
But how modest they were: this is no ordinary TEST BED, this is the Sidewinder, a go-anywhere machine that was even plated for road use. No small feat for a vehicle that has a body that's somewhat similar to an ant's: the front had the passengers and front axle; middle contained the powertrain; and a rear cargo box, rear axle section.
This sort of innovative thinking in 1964 is characteristic of General Motors of the time…but only because it had hired some of the best engineers and designers on the planet. In this case, you're looking at the work of Vic Hickey.
He'd later help design the Lunar Rover, which qualifies him as an "off-road" as well as an "off-planet" expert, as well as the Baja Boot, which will surely feature here eventually. The reason for designing such a seemingly complex vehicle is twofold: first, to see how far the military can extend its capabilities off-road with wheeled vehicles, and second, to explore the possibility of swapping powerplants in the field.
As it sits, how does this sound? Up to 96 km/h (60 mph) on land; 38 cm (15 inches) of ground clearance, and 60 degrees of approach and departure—in comparison, a new Jeep Wrangler Rubicon gives you an approach angle of 42 degrees and a departure of 32.
The capabilities are impressive, but more so the idea of easily swapping out a vehicle's powertrain. The prototype had a 215 cubic-inch Buick V8, two-speed automatic transmission, and a two-speed transfer case, but in the future, the centre module could just as easily be a turbine that runs on natural gas or an all-electric version to launch a surprise attack. Some sources online (linked below) say it's also amphibious, but this is a point not mentioned by General Motors in any material that I could find.
And because Hickey was a do-it-yourself kinda guy, apparently all of the Sidewinder's components were off-the-shelf—apart from its body, of course. The prototype would go on to inspire the Lunar Rover, apparently, and Hickey would eventually lend his talents to the truck later known as the HMMWV.