If you're interested in buying a used car, you've probably seen sellers or dealers advertising certain vehicles with all-highway miles. At first, this may seem confusing: Since highway miles are at high speeds, wouldn't this be a bad thing? Or is it the other way around: Are city miles more challenging because of the constant stopping and starting associated with driving in town? We have the answer.
Highway vs. City
There's no question that highway and city miles affect a car in different ways. In city driving, for instance, vehicles are constantly stopping and starting, which means they use more fuel. City driving also typically involves rough roads and potholes, giving a car's suspension more of a workout. On the highway, roads are smoother but speeds are higher, which means the engine is constantly working and never at rest.
So which is easier on a car? The answer is highway driving. While it might seem like the low speeds and occasional idling associated with city driving are easier on a car than high-velocity highway travel, the truth is exactly the opposite.
One reason is that city driving has a wide range of varying road conditions. While most highways are fairly smooth, city roads can be pockmarked, potholed and full of all types of issues and problems that you'll never encounter on a highway, from rocks to speed bumps. The jarring ride gives the suspension a workout, and the same goes for other parts of a city-driven car as it bounces around on the street.
Stopping and starting is also very taxing on most cars. While an engine will typically sit at one cruising speed on the highway, city driving requires constant speeding up and slowing down. The result is that a city-driven car's engine is constantly working, as are the brakes and the transmission.
City driving is also challenging to a car because of all the potential issues that can occur when you own a vehicle in a large city. There are more cars on the road, which means more possibility for an accident. There are parallel parking spaces, which increases the potential for wheel damage, and regular parking lots, which means you'll get the occasional door ding. And of course, there's also vandalism and theft, two issues you won't encounter on the highway.
How to Tell?
Now that you know highway driving is better on a car, you might be curious how to find out which vehicles have spent more time on the highway and which have spent most of their lives in the city.
Fortunately, there are a few easy ways to tell. One is the odometer reading itself: A fairly new car with unusually high mileage will usually be a highway vehicle. For instance, a 1-year-old car with 50,000 miles on it probably spent the vast majority of those miles on the highway. Few drivers can travel 50,000 miles in one year solely within stop-and-go traffic, unless they're driving a taxi cab or a police vehicle.
Another way to tell is to check the body of a high-mileage car. Are there any dents? Any wheel curb rash? Are there any scrapes? If the answer to all of these questions is no, then the car probably hasn't spent much of its life in the city, where it would be subject to parking lots, curbs and other drivers.
But if you want to be really sure that a car has mostly covered highway miles, check with a mechanic. This is a good idea anytime you're buying a used car, but it's especially a good plan if you're thinking about a high-mileage example. A mechanic can examine a car's suspension and other components to determine wear, and he or she can let you know whether the car has been babied on the highway or thrashed on city streets.