A few weeks ago, I went to the amazing Auburn Cord Duesenberg Automobile Museum in Indiana, where I learned about an axle that has not just one gear ratio like in pretty much all modern cars, but two.

In the automotive world, especially when it comes to off-road trucks and SUVs, differentials come up all the time. Is your differential locking, limited slip or open? Do you have a transfer case? One ...

Scientific American is part of Springer Nature, which owns or has commercial relations with thousands of scientific publications (many of them can be found at www ...