Gearheads might be aware of piston skirts, but their exact function isn't always clear to those outside engineering. Here's the lowdown.

It goes up, compresses a violent explosion, and goes down. A piston's job is easy enough to understand, but if you examine what it's required to do, you may be amazed it works at all. Think about ...

As hard-chrome plating has fallen out of favor, hydraulic-cylinder manufacturers have developed alternative coatings and platings. Here is how they affect seal performance and life. • Hard-chrome ...