Owners have long joked that cars are designed to last
a couple of days past their warranty period, then fall apart. Well, it isn't much of a joke anymore. Engineers using powerful computer modeling can forecast the life span of parts more accurately than ever. If those parts prove weak, they are reinforced during development;
if they are too strong, they are slimmed down to save weight or cost. The result is that modern cars boast superb reliability for their designed lifetimes. They require minimal maintenance and return excellent performance. But when they reach the end of their design life span, many of those parts have simultaneously reached the end of their road.
This doesn't mean that one day you'll walk out to the driveway to find Old Faithful snapped in two. The wheels aren't going to fall off or the brakes stop working. Such fundamentals are designed to last indefinitely, given normal maintenance. But everything else — nonessentials such as switches, upholstery, paint, rubber parts, trim, plastics, door hinges and so on — is not designed to last forever. The nonessentials are designed to last the "lifetime" of the car.
Just how long is a car's lifetime? It varies, but 150,000 miles or 10 years is typical. Clearly, cars can serve longer than this. But more typically, a decade down the road, when you
suddenly realize the headlights are yellow, the upholstery is starting to unravel, the window switches have failed and the clear-coat paint is peeling into alligator skin, it is unequivocally time to move on. To do otherwise is shoveling against the financial tide.