When Do I change my Oil?

Motor oil technology has gradually progressed since the days of the earliest automobiles. In those days, standard motor oil drain intervals were between 500 and 1000 miles, and motorists had to switch viscosity grades with the changing of the seasons. The development of oil filtration and additive technology in the 1930s allowed drain intervals to increase to 2000 and later 3000 miles, while the development of viscosity modifiers in the 1940s allowed the formulation of multi-grade oils that could be used in both hot and cold temperatures.

The technology for extended oil drains is obviously available, but until now, the major oil companies have had other agendas. Marc Graham, who is president of Pennzoil-Quaker State-owned Jiffy Lube International, was quoted in a 2001 Lubricants World interview as saying, "At [PQS] we use a number internally that if we [shortened the drain interval] by 100 miles [for each car serviced], it would mean an additional $20 million in revenue for the company." He also explained that "if we could move our customers to get one more oil change per year, it's worth $294 million for the oil change alone and $441 million in revenue, when you include the ancillary products and services customers typically buy along with the oil change."

Vehicle manufacturers in Europe have been recommending extended oil drains for years. In fact, the average drain interval in Europe is 10,000 miles. Vehicle manufacturers in the United States are definitely coming around to extended oil drains as well. Most owners manuals from recent model vehicles recommend 5000 to 7500 mile oil drain intervals. In addition, oil life monitors have become increasingly common on today's vehicles, allowing and encouraging motorists to increase drain intervals up to 12,000 miles, even when using conventional oil. Vehicles equipped with an oil life monitor no longer recommend oil changes based solely on mileage. The system measures engine operational data such as temperature, revolutions and speed to determine when the oil is nearing the end of its life.

As time goes on, more and more equipment managers are exploring the use of extended oil drain intervals. While there are many cautions that accompany establishing an extended drain program, they can be more than offset by savings in maintenance costs and increased uptime. It has been reported that in the not-too-distant future extended intervals will be commonplace. Several engine manufacturers are said to be considering new recommended oil and filter change intervals.