Ask a Technician: Are highway miles better for my car than city miles? -

When it comes to wear and tear on your vehicle, not all miles are the same. City driving, due to its stop and go nature, leads to more wear and tear on the engine, transmission, and other critical parts. Learn more about highway versus city miles and their effect on your vehicle from our skilled service team at Sheehy Nissan of Glen Burnie

Gas mileage. Many drivers become aware of a difference in city miles and highway miles when they go to purchase a car and notice the miles per gallon rating. A vehicle can generally be expected to get significantly more miles to the gallon driving on a highway than driving in the city. This difference in miles per gallon provides clues as to why highway miles are better for your car than city miles—and it has nothing to do with magic gasoline being sold at freeway entrances.

Efficient and inefficient miles. A car gets better gas mileage on the highway because highway miles are more efficient than city miles. How Stuff Works says that the “sweet spot” for maximum fuel efficiency “is in the range of 40-60 mph” for most cars, and you're much more likely to be close to this zone while driving on the highway. City driving also requires more stopping, which means more going, which means a car's engine spends a lot less time at efficient speeds and a lot more time revving up after a stop sign or stoplight. It is also much more likely your vehicle is able to "cruise" on the highway without having to slow down or brake.

Stopping and going. The stopping and going doesn't just increase wear and tear on the engine. Other crucial parts of an automobile are worn faster through stop-and-go city traffic. An obvious component is the brakes. There's a reason drivers take the highway if a highway route is available, even if it means traveling a few extra miles. It's because you don't have to stop every few seconds or slow down because some individual decided to go 19 miles below the speed limit (if your heart rate just accelerated at the mention of following someone going 19 miles below the speed limit, take a deep breath.).

The transmission. It costs a lot of money to replace a transmission. On the highway, you're going at a steady speed, oil pressure is higher, internal engine parts are better protected, and engine temperature is stable. In addition, your gears aren’t shifting up and down constantly as they would with stop-and-go driving. Transmissions only wear when they shift. Therefore, highway driving causes less wear and tear on your transmission.

Buying a pre-owned vehicle. Because there really is no way to truly know how many of an automobile's miles were highway and how many were city, your astute knowledge of highway miles can only be applied to maintenance on a vehicle you've been driving. If you're worried about the wear and tear on a vehicle you want to purchase, you'll want to buy a pre-owned vehicle that's been certified by a reputable dealer. Our dealer mechanics give all vehicles a thorough inspection, so you can be sure you're getting a car that will give you what you need—be it on the highway or in the city.