We take our differentials for granted, right? Of course, we expect our vehicles to navigate turns without scrubbing the inside tires or hopping the outside ones. But how does a diff do that? Look for ...

Let's be honest, the average person has never thought about whether differentials even have fluid. They're not like engines, which require oil changes after about 5,000 to 10,000 miles (or 12,500 if ...