The GM Oil Life Monitor System is not a mileage counter. It is actually a computer based software algorithm that determines when to change oil based on engine operating conditions. The computer continuously monitors engine-operating conditions to determine when to change oil. Over the years, millions of test miles have been accumulated to calibrate the system for a variety of vehicles. The system was first introduced in 1988 and is now on more than 10 million GM vehicles.

The beauty of the GM Oil Life Monitor System is that it will automatically adjust the oil change interval based engine characteristics, driving habits and the climate in which the vehicle is operated. For instance, mild highway driving in a warm climate will maximize the interval between oil changes. Depending on the vehicle, this could be in excess of 7000 miles and as high as 12,000 miles. On the other hand, short trip driving in cold a climate may limit the oil change to 3000 miles or less. In general, most people that drive a combination of city and highway schedules find that the GM Oil Life Monitor System will indicate an oil change every 7500 to 8500 miles. The GM Oil Life System is that it calculates for severe climate use and
determines the oil change interval just as it does for trailer towing as well as stop and go operation. There is no need to adjust the oil change based on climate, as well as vehicle use.

The 3000 mile oil change is very conservative approach to maintaining your vehicle that dates back to 1968. Many advancements in engine and oil technology have been made since then. These advancements allow engine oil drain intervals to be increased without risking harm your the engine.