Whats the truth of it? Are extended drains better or should we stick with the traditional shorter drain intervals? What are the arguments for and against? Are they credible or marketing hype?

Whos for extended drains? That is a good question, and the answer is OEMs, consumers and other interested groups.

OEMs. For years, most passenger car owners manuals called for either 7,500 mile (normal) or 3,000 mile (severe) change intervals for engine oil. In the late 1980s the computer made its way into the ignition and emissions control systems of the automobile. It wasnt long before other uses became apparent. By monitoring engine speed and oil temperature, automakers found it was possible to set up an algorithm to determine when oil should be changed.

At the September 2005 World Tribology Congress in Washington, D.C., James Spearot of General Motors reported that his companys on-board Oil Life System (OLS) would allow drivers of GMs 2005

model year vehicles to average 8,500 miles between oil drains. GM has removed the references to oil change mileage in its owners manuals in favor of the OLS system, which alerts the driver when a change is needed. The choice to do so was based on research showing customer demand for reduced maintenance and convenience, as well as environmental benefits such as less oil handling and reduced need to dispose of used oil.

Spearot was careful to say that warranty protection would not be compromised, and that changes to greater oil change intervals – perhaps as long as 40,000 miles one day – would be rational and not done in a precipitous manner.

Automakers continue to put a lot of pressure on the oil and additive industries to upgrade oil quality. Reduced volatility and phosphorus levels as well as increased oxidation resistance and upgraded fuel economy are all features with which the oil and additive industries struggle – not to mention lower and lower viscosity. Theres little doubt that these initiatives result in oils that are more robust.

The OEMs are most concerned that their vehicles will still meet government fuel economy and emissions standards even after they have been on the road for some time. The recently signed Energy Bill of 2007 requires a 40 percent improvement in fuel economy by the year 2020, as well as reductions in greenhouse gas emissions. Systems such as GMs OLS and Mercedes-Benzs on-board maintenance monitor help make it possible to meet these requirements with confidence.

Vehicle Owners. The typical motorist is less concerned about maintaining his car (possibly because it is more likely to be a lease) and is more concerned with convenience, which is a big part of his equation. Hes more likely to keep his current car for three to four years and then trade it in on a new one. Even with 10-minute oil changes, it does take time out of his schedule. Thats one reason why the combination quick oil change and car wash outlet has made such an impact. The inconvenience is lumped together, representing only one segment of downtime. With the OLS, he is even happier that he doesnt have to spend as much time and money on oil changes.

Others. There is an environmental issue that bears on the oil drain interval question. Disposal of used oil, particularly from do-it-yourselfers, is a serious issue in the United States. The following breakdown of used oil disposal shows the extent of the problem:

Forty percent is dumped on the ground or down the sewer, 20 percent is thrown out with the trash, ending up in landfills, 6 percent is burned, 19 percent is reused for miscellaneous purposes, and 14 percent is recycled.

The Environmental Protection Agencys website shows the following facts about used oil:

– The used oil from one oil change can contaminate 1 million gallons of fresh water – a years supply for 50 people.

– Used motor oil is insoluble, persistent and can contain toxic chemicals and heavy metals.

– Its slow to degrade.

– It sticks to everything from beach sand to bird feathers.

– Its a major source of oil contamination of waterways and can result in pollution of drinking water sources.

Obviously, if there is less used oil, these problems are reduced.

The question of crude oil dependence is also brought up as an argument in favor of extended drains. If drain intervals went from the current 4,300 miles to 8,500 miles, engine oil use would be cut in half. NPRA data show that passenger car engine oil sales were about 700 million gallons in 2006. Reducing that to 350 million gallons of oil would free about 8.3 million barrels of crude oil per year. Annual U.S. crude use is around 6.12 billion barrels so the reduction amounts to about 0.1 percent of crude demand. Not a big number in fact, but with crude costing $100 a barrel, its a tiny step in the right direction.

The Other Side of the Table

There are some supporters in favor of keeping oil drain intervals as they are. They are primarily oil service providers, Do-It-Yourself consumers and oil marketers. Lets look at them.

Oil Service Providers. Their position is that a shorter drain interval is insurance against a bigger problem later. This argument is advanced by car dealers, garages and 10-minute oil change outlets. The basic premise is that changing your oil regularly minimizes the problems of low oil levels or risk of oil so dirty that it can cause deposits to form in the engine. It is, coincidentally, a good way to sell more oil.

In a newsletter designed by Blue Flame 6 Advertising and supplied to car dealers to share with their customers, a recent article entitled Get Cooking with Oil made the following comments:

The common consensus is that motor oil should be changed roughly every three months or 3,000 miles, whichever comes first. Naturally, you can easily obtain precise information on your vehicles specific needs by consulting your owners manual.

And whats the easiest way to keep your car running strong? Take it to your trusted dealer, of course. Your dealer knows your car inside and out, and, in under an hour, can drain your old, sludgy oil, and replace it with the fresh, lubricating stuff.

For a few bucks and a few minutes at your dealers service department, you can keep your engine running strong for another 3,000 miles, and save yourself thousands in engine repairs.

Another advantage of a shorter oil drain interval is that the underside of the vehicle can be inspected for other problems such as leaking shock absorbers or brakes, worn tires and exhaust system deterioration. Speaking from personal experience, I was saved from a roadside breakdown by a quick-lube attendant who noticed that the serpentine belt on my Nissan Quest was very frayed and close to failing. They changed the belt at a reasonable price and I was quite happy.

Do-It-Yourselfers. The DIYer is more conscientious about his oil changes. He takes great pride in his transportation and wants to keep it in the best running order possible. His motto is, Spend pennies now to save dollars later. His philosophy coincides with the car dealers and service providers position but, obviously, not for the same reasons.

There is even a mystique about crawling under the car to change the oil that says, Im taking care of my baby!

Oil Marketers. Like any good marketer, the oil companies want to sell more of their product. Most have supported the 3,000-mile drain position without fail and also try to meet the desires and needs of the longer drain population by producing special engine oil products such as high-mileage oils, synthetics and oils touted as extended-drain formulas.

If all oil drain intervals magically went from todays average of 4,300 miles to 8,500 miles, the volume drop in engine oil sales would be about 350 million gallons per year. This reduction in oil volume would come at a cost. For a small blender it may spell the difference between staying in the business and getting out of it. For the rerefiner, it may mean that there was less interest in waste oil gathering and subsequently less feed for their plants. It would also be a loss to retail merchants who sell to the DIY market.

At about $2 to $2.50 per quart, the revenues that would be lost are on the order of $2.8 billion to $3.5 billion a year. All of these are significant impacts.

So, whos right? Do the benefits of improved oil chemistry and technical developments in on-board oil monitoring make your choice longer drain intervals? Do you consider your transportation a member of the family and to be pampered? Do you want the extra protection and inspection of shorter drain intervals? When I started this article, I was a member of the 3,000-mile club; but after researching the situation, Ive changed my mind and will rely on my OLS system to tell me when to change. Whats your choice?