Most vehicle manufacturers recommend changing the oil once a year or every 7,500 miles in passenger car and light truck gasoline engines. For diesel engines and turbocharged gasoline engines, the usual recommendation is every 3,000 miles or six months. If you read the fine print, however, you’ll discover that the once a year, 7,500 mile oil change is for vehicles that are driven under ideal circumstances.
What most of us think of as “normal” driving is actually “severe service” driving? This includes frequent short trips (less than 10 miles, especially during cold weather), stop-and-go city traffic driving, driving in dusty conditions (Arizona), and driving at sustained highway speeds during hot weather. For this type of driving, which is actually “severe service: driving, the recommendation is to change the oil every 3,000 miles or six months. For maximum protection, most oil companies say to change the oil every 3,000 miles or three to six months regardless of what type of driving you do.
As an engine accumulates miles, blowby increases. This dumps more unburned fuel into the crankcase which dilutes the oil. This causes the oil to break down. So if the oil isn’t changed often enough, you can end up with accelerated wear and all the engine problems that come with it (loss of performance and fuel economy, and increased emissions and oil consumption). This can also lead to engine damage that in most cases end up being very costly.
Preventative maintenance is what Martin’s Auto Repair knows prolongs the life of your engine and lowers the overall cost to maintain your automobile. We encourage you to ask us how to best maintain all aspects of your automotive care.