You know you've thought about jamming your car's transmission into reverse at speed, "just to see what would happen." Of course, you didn't, because your lizard brain lost out to your conscience and your pocketbook.
But it's 2017; you don't have to do stuff like that because you can be sure someone's already done it, and put it on YouTube for you to watch.
Here's the setup. An unnamed reverser is driving a second-generation Ford Ranger at around 40 mph (according to the hed of the YouTube video). You hear some grinding, then the clutch goes in, there're a rev, and then backward-gear engages and the wheels' directional rotation reverses. Then there's one hell of a smoke show. Simple as that.
Takeaways? The truck, which sounds like it's a 2.3-liter four-cylinder model, takes the shift in relative stride, proving—if nothing else—that the Mazda M50D transmission is a pretty stout little manual box.