Increased oil change intervals


I’m curious @Barkydog. When you change oil at 5000 miles, what is the remaining oil life?


I have no idea of remaining life, just know it was done before needed rather than after.


Well don’t you have to reset the monitor? The car doesn’t know when you change oil otherwise. I think we’ve had this discussion before. My Pontiac manual says if the OLM gets reset by mistake or whatever, the oil needs to be changed at 1500 or 2000 miles or something like that. It just keeps going down to zero if you don’t reset it. I don’t know what happens then-maybe bells and whistles or I’m reported to Onstar or something for abuse.


That’s very ironic, considering their product is certainly not priced cheaply


can’t you press a few buttons and find out the remaining oil life percentages?

Even on our fleet’s low trim level gm trucks, we can do that


Depending on the age and model of your GM car, the answer could very well be “no”. And the same is true for many Toyotas.


One other thing to consider is oil capacity. 25 years ago a 4 cylinder engine held 3.5 to 4 quarts of oil. The gas V8 in a Ford pickup held 5. Now a 4 cylinder engine may hold 6 quarts and a smaller V8 Ford holds 7. Simply having more oil to hold contaminants in suspension, dissipate heat, and maintain additive packages allows longer change intervals.

A BMW 3.0 liter engine may be able to go 10,000 miles on an oil change, but it requires a $25 oil filter and 9 quarts of Euro spec synthetic oil. A Ford 3.0 engine uses a $6 filter and 5 quarts of plain old 5W20.


Most of their oil has the API starburst symbol with SN classification.


Our 2003 Silhouette Premier has an OLM with push button access and reset. Our 2009 Cobalt LT and 2010 Cobalt LS have a similar system. If the Cobalts have it, I think every 8 year old GM vehicle must have it.


My '14 Highlander’s oil change recommendation is 10k miles. No way in hell am I going to wait that long. 5k oil changes have been proven to keep vehicles running well pas 250k miles. 10k oil changes are too new. I’ll let someone else experiment.

Wifes '07 Lexus 3.5L V6 (5w-30) Toyota recommends 5k miles.

My '14 Toyota Highlander 3.5L V6 (0w-20) Toyota recommends 10k miles.

Sons '11 Mazda 3 2.6 I4 (0w-20) Mazda recommends 5k miles.


They’ve been around for about 20 years now, depending on the auto manufacturer


The Opel car I rented in England had a 20,000 MILE!!! interval or twice a year.

Ludicrous but it has a larger oil sump and European spec additive package for the oil…

Just the same, I would change it at half (10,000 miles) if I lived there.

We’re tryin g to maximize ENGINE LIFE rather than OIL LIFE!.


That’s very interesting . . .

Considering many europeans drive far less than americans, it would take a few years to reach 20,000 miles

Since it’s always mileage or time, whichever comes first, in that situation I personally would go by “twice a year”

By the way, are you sure you wrote that correctly?

If you performed the oil change twice a year, that would pretty much negate the whole point of the extended oil change interval

Did you in fact mean every 20,000 miles, or every 2 years, whichever comes first . . . ?

And you bring up a very good point about he larger oil sumps. For several years a Benz V8 oil sump held just over 8 quarts, while a typical GM small block oil sump held just 5 or 6, depending on which generation we’re talking about


Still very limited and IMO not enough data to get any meaningful information on how well it is. 5k has plenty of data.


As you said, it’s a matter of opinion, and mine happens to vary. To clarify, I think there is enough meaningful information

But I personally stick to 5k oil change intervals, using full synthetic


Some European auto manufacturers have extended oil life to 15,000 miles in favorable conditions. They do it with significantly larger oil sumps and that special European oil grade of synthetic oil. I wouldn’t do it in my cars, but the cars with OLMs say the lifetime is between 7500 and 10,000 miles, depending on the car. OLMs have been around for 30 years now and I think that I should long enough to trust them and the car company that is willing to sell them. This won’t help people that don’t check their oil level, but if you don’t check oil level, maybe you don’t deserve to have a car for longer than 100,000 miles before it seizes.


Sorry, I stand corrected; it said 20,000 miles or ONCE a year ! I got the other info from the owner’s manual!

This car was built in Germany since GM no longer builds cars in England. It was rebadged as a Vauxhall to soothe British pride and sensitivities. Only the manual was printed in England!


Let’s assume most europeans don’t accumulate 20,000 miles per year

So that leaves once a year, which doesn’t sound catastrophic, considering the high quality full synthetic oil required for such an engine

It would probably average out to 6 to 8 thousand miles per year, fairly reasonable

However, it would make me nervous if somebody DID drive 20,000 miles per year, and chose to wait until the oil change reminder light came on

Then again, europeans typically don’t expect to rack up 250,000 miles on a vehicle, like many americans do . . . those that take care of their vehicles, that is :smiley:


Let me tell you again. People here say, well, it costs too much to test your oil, it’s cheaper to just change it.

The oil tests don’t just test the oil for remaining life. If that is all they did, yes, it’s cheaper to simply replace it.

They check for various contamination things. Essentially, it tells you if any part of the motor has a problem. Valve train wear produces certain contaminants. Ring wear, different contaminants. Blow by, they can and will tell you. Antifreeze internal leak, they tell you.

Once you fully understand the results, you also understand it’s like having a microscopic mechanic wandering around your motor looking at everything.

And, also the amount of additives remaining in your oil.

If you do this once for each drive cycle, that is, how you drive the car, summer long trips or short trips; winter short trips, you can then estimate how often to change the oil during that drive cycle. So, you do not need to do an oil test every time you change oil.

Several years ago, I got tired of the constant guessing how often to change oil, and had the oil tested in my 2002 Sienna at around 8000 miles, I forget now. I learned that not only was my motor in great shape, but the additives would be good for at least 11,000 miles.

I was at the time driving 25,000 miles a year, almost all long distance highway driving, outside the Snow zone, and using Mobil-1 EP. After that, I changed the oil at around 7000 miles.

If I had moved back into the snow zone, or changed my drive cycle, I would have tested it again.

From time to time a poster will pontificate, if you really care about your car you will do what I do…

Actually, if you really care about your car, you will either change the oil more often than recommended, OR will get the oil tested and find out what is really happening. No more guessing.


Every time someone tells me that they had their engine oil analyzed, I ask them if they also had the transmission fluid analyzed.

That’s when the crickets start chirping in the background.