Pretty much everyone knows that a car needs its oil changed every few thousand miles. But there is a lot more to maintenance than fresh oil. For example, there are four other major fluids that need to be drained and replaced less often.
Transmission fluid allows the transmission to shift smoothly. New transmission fluid looks like thick strawberry syrup. Aging fluid gets darker, thicker, and can smell bad, and really old fluid may look sludgy or tarry. A car with very old fluid won’t shift smoothly. A car that does not have enough fluid may lurch, shift badly, or refuse to shift at all.
Power-steering fluid lubricates the steering mechanism so that steering is easy. New power-steering fluid is amber like dark honey. As it ages, power steering fluid becomes thicker and sludgy and may smell bad, much as transmission fluid does. A car with aged or not enough power steering fluid will become increasingly harder to steer and control.