I already know how to reset it, so this isn't asking that question.

I don't have an owners manual to my car and all searches I look up bring back results on how to reset the darn light.
I change my oil religiously every 3000 miles and am just wondering because every other oil change, right after I get done changing it, the change oil light comes on.

What's the interval on this?

 

The car's computer monitors the driving conditions to determine when you should change your oil. I think the computer takes into account whether your trips are short distances or long, outside temp, engine temp, rpm, etc. So, the computer is probably calculating around 6,000 miles between oil changes for your driving habits.

 

^ so is it good to chang it every 3000? Or just go by the light?

 

I think there was a big discussion on this topic here recently. Unless I'm confusing it with the Jag Lovers Forum I also monitor. Getting old sucks...

Short version... Most folks seem to think that the '3000 mile rule' was created by the quick-lube-industry. Most modern engines are fine going around 5k-6K between changes. But as mentioned above, that does depend on the type of driving. Mostly short trips around town, 3K is probably about right. But with longer trips or a mixture of short/long you can generally extend that to about 5K-6K miles. Your car's monitor should give you the 'Change Engine Oil' warning at about the 80% point (about 20% oil life remaining). And the monitor doesn't know that you've changed the oil unless you reset the monitor; it's not actually testing the oil in any way. It just monitors all the parameters and calculates how long the oil should last.

 

From the May 2003 GM Techlink publication

How often should engine oil be changed? 3,000 miles, 5,000 miles, 7,500 miles, 10,000 miles? Actually, all of these are correct, depending on operating conditions. Oil life is affected by many factors other than just miles driven. The type of driving, temperature, and engine load all play a part.

That’s why GM has developed the GM Oil Life System, an electronic watchdog that keeps track of all these variables and notifies the driver when it’s time to change oil. This system has become standard equipment on nearly all GM products since 2000.

Briefly, the Oil Life System is programmed with a certain number of engine revolutions. As the engine runs, this number is reduced until it reaches zero, and the Oil Life light or message comes on. But there’s more. Operating the engine under low or high temperatures, and under high load conditions subtracts (penalizes) extra revolutions, so the light comes on sooner. Changing engine oil according to actual need rather than an inflexible schedule provides several benefits. First is simplified determination about when to change oil. No more decisions about normal conditions vs. severe conditions. Second are reduced operating costs for GM’s customers, who now have to change oil only when it’s needed. Third is minimizing the amount of used oil that must be disposed of. And fourth, engines will always be running with sufficiently fresh oil, for long life.

Traditionally, the vehicle maintenance schedule has been based on miles or time, while the oil change interval is now based on the GM Oil Life System.

When the change engine oil light or message comes on, it means that service is required on the vehicle. It should be serviced as soon as possible within the next 600 miles. It is possible that, under the best conditions, the engine oil life system may not indicate that vehicle service is necessary for over a year. However, engine oil and filter must be changed at least once per year, and at this time the system must be reset.