A large number of people in Rutherford County drive to Nashville and back every working day. It is one of the defining facts about living here, and it does specific things to a car that mileage alone does not explain.
Stop and start traffic is the hard part, not the distance. Thirty miles of open highway is close to the easiest thing a car can do. Thirty miles of accordion traffic on I-24 is close to the hardest, and the odometer records them identically.
Brakes. The obvious one. Continuous light braking in slow traffic puts far more cycles through a set of pads than the same distance at a steady speed. Commuters routinely need brakes at mileages that surprise them, and there is nothing wrong with the car.
Transmission fluid. The less obvious one, and the more expensive. A transmission cools itself partly through airflow and partly by not working constantly. Crawling traffic gives it neither. Fluid runs hotter for longer, degrades faster, and the manufacturer’s interval assumed conditions you are not driving in.
Cooling system. An engine sitting still in August traffic is working harder to stay cool than the same engine at seventy, because there is no air moving through the radiator except what the fan pulls. Marginal cooling system components fail in traffic, not on the highway.
Exhaust, in the other direction. Long commutes are good for exhaust systems, because the system gets properly hot and stays there, which boils out the condensation that rots mufflers from the inside. The short-trip driver has the exhaust problem. The commuter mostly does not.
Tires. Constant small steering corrections and stop-start loading wear tires unevenly, and alignment matters more for a commuter than for someone doing the same mileage on open road.
What to do about it. Treat the severe schedule in your owner’s manual as your normal one, because that is what it was written for. If your car has more wear than its age suggests, and those miles were spent between here and Nashville, that is the explanation.
Tell us how you drive when you bring the car in. It genuinely changes what we recommend, and it changes it in the direction of fewer surprises.
Stones River Auto and Exhaust, 1601 Flat Rock Road, Murfreesboro. Monday through Friday, 8:00 AM to 5:00 PM.
