Every other day or so, I take my dogs on a long walk. They enjoy the exercise and I get a chance to think about work. The first part of our walk takes us along a busy street before turning onto a state trail that meanders through the countryside. It's bucolic and pastoral, but the part that frequently interests me is the stretch of busy highway. Beyond the soda cans, fast food wrappers and cigarette butts, one occasionally finds car parts. What's interesting, compared to a few years ago, is how seldom vital bits and pieces fall off our cars these days.
It wasn't always like this. In the past decade or two, a walk along any highway would provide an automotive archeologist with a treasure trove of mechanical detritus. Car parts large and small used to litter the shoulders, and it took an educated eye to identify and classify the components shed by a society in motion.
Most common were mufflers. These rusted cylinders, often with portions of their crumbling tailpipes still attached, came in two varieties: those that had fallen from their mounts and came to rest (reasonably intact) on the verge, and those flattened by subsequent vehicles until they resembled some form of deconstructionist art. You hardly ever saw catalytic converters-they were heavy enough to require substantial mounting systems. Today, with expensive stainless steel exhausts and the requirement that emissions control systems last up to 100,000 miles, you don't see so many mufflers.
Second most common were fan belts, more properly called accessory drive belts. These were apparently designed to fail at frequent intervals, and seeing the long snake-like bands of rubber lying on the highway was proof that the nation's economy was designed to be self-perpetuating. Fan belts are much less common on today's cars, having been replaced by the serpentine belt, which is a single long belt that powers all the vehicle's accessories. Serpentine belts are typically reinforced by super-strong materials and are wider, spreading the load over a broader area, so the likelihood of failure is much less.
Spark plugs used to be such a common sight that I've known grown-ups who, when they were kids, collected and categorized them by brand and type. Spark plugs can be explained. As cars have become more complex and engine bays more crowded, the probability of a dropped spark plug hitting the ground is pretty low. They usually lodge into some inaccessible nook where they remain for years until just the right bump dislodges them. You see fewer today because so few people work on their own cars, and professional mechanics are-in theory, at least-more careful and less likely to drop a part into the abyss.
Most amazing was the number of seemingly indispensable parts: oil filters, fuel pumps, brake discs, ball joints, shock absorbers, distributor caps and brake pads. Yet I've seen all of them, a veritable spare parts warehouse, sitting by the roadside. How can a car make it home without these vital pieces? Why aren't there more cars parked on the side of the road? Why aren't tow-truck operators wealthier than plumbers?
Perhaps one reason why less parts fall off these days is the vast improvements made in fasteners. Graded high-strength cadmium-plated bolts with nylon lock-nuts now hold most accessories and suspension parts. And these bolts are often coated with an anaerobic thread-locking compound that guarantees no movement, even when exposed to constant vibration. And bolts are tightened now by torque-sensing robots, ensuring they are stretched and conditioned just the right amount. If you see a random bolt at the side of the road today, chances are it's rounded-head-a carriage bolt used to attach some aftermarket accessory.
Since we're comparing the past and the present, the near-total absence of miles of thin cassette tape draped across the weeds and blowing in the wind can be directly attributed to compact discs. CDs are virtually indestructible, so less prone to jamming and being tossed out of the window.
I'm not glorifying the days when bits and pieces regularly used to fall from my old cars and motorcycles. Quite the opposite. Some modern fastening technology can be applied to our old crocks to help keep them from shaking themselves apart. Still, I like to imagine archeologists, a millennium or so in the future, sifting through the flotsam of our civilization. They'll examine the strata, identifying the periods, layer by layer, when mufflers and spark plugs dominated our roadsides, comparing them to the eight-track and cassette-tape eras. Treatises will be written, theories will abound, and if they're lucky, maybe the decrepit remains of a Porsche 911 or VW GTI will still exist to help them understand what these machines meant to us.