Oil Changes . . . How often?

One of the tricks of the trade is to know when the manufacturer gets it wrong.

That happens more frequently than you think, and often, it takes a rash of engine failures to have the engine makers and oil industry do a collective "opps" and revise a standard.

Many of these cars mentioned in the article below followed the manufacturer recommendations, and still had problems.

Chrysler has a serious sludge problem with the 2.7-liter V-6 engine used on some of its Concordes and Sebrings and also on some Dodge Intrepids and Stratus in the 1998-2002 model years

http://www.nytimes.com/2007/02/04/automobiles/04SLUDGE.html?pagewanted=all

So did...

Dodge, Toyota, Lexus, Volkswagen, Audi and Saab. In fact, every manufacturer had a problem if we went back far enough.


So while the manual, especially the severe duty part, should be followed to the letter, occasionally, one need to exceed the manual recommendations.

The most foolish thing is to blindly rely on a computer engine monitor that tries to either use a basic sensor (mostly optical) or computer derived guesses from operating conditions and history when it is right to change oil.

Now, if extending the interval is backed with oil analysis from a top quality lab, that is another issue.

If the computer tells you it is not necessary, and you are at the owners manual severe service recommended interval, it would be prudent to change it at that point.... just in case some freckle face kid who wrote the code got the software written wrong, or misplaced a decimal.

Software errors happen very frequently.

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I recommend a very different oil change regime from the manual for new vehicles:

Change oil and filter (use mineral to save costs) at these intervals:

250 miles
500
1000
2500
5000

Then follow manufacturer recommended.

This routine will only make money for you if you keep a vehicle past 100,000 miles --- but will greatly extend engine life.


If money doesn't matter, synthetics that are name brand are inherently better than mineral, especially for cold starts.


Now onto oils.

Oils are graded voluntarily by the distributor. Just because it says API-SN doesn't mean anyone have actually tested it independently and your batch is any good.

Hence, relying on a name brand is prudent. Do you really trust a no name brand with an engine that can cost $5,000 or $15,000 to repair?

Always use the latest available API grade.

For those who remember, API started with SA and is now on SN.

Each iteration were meant to solve different problems that were not obvious --- and many of them were done because of "opps".

Looking retroactively back at the standards tells you a lot about how oils are better or worse.

Oils are backward compatible -- but only to a point.

Hence, always use what the manual recommends or better.

I think use of full synthetic like mobile one, is good for towing applications due to its ability to hold up in high temperature situations. IMHO 5,000 mile intervals is fine. I've done this with my truck since new and have 146,000 trouble free miles.

....and I pour in full synthetic. Big debate for another time, but it makes me feel better.

Your Dodge will tell you when it's time to change the oil, changing it prior is likely a waste. It takes into consideration the time spent on tow/haul mode, kms yadda yadda.. That is what the dealer told me. It's not always at standard intervals.

downtheroad wrote:
No additives.
Follow Dodge's recommendations in the manual. They built it and they warranty it.

You could use the "severe service" guidelines because you are mostly towing.

X2

Use the oil grade recommended.

Unless your vehicle requires any additives, I wouldn't waste money on adding them. Your best bet is to read the manual and lean towards the "severe service" maintenance page. With modern oils and a new engine, 5,000 mile intervals is probably okay. Oil is cheap, I usually try to change my oil every 4,000 miles. My oil is still pretty clean when I change it, so I know that my interval is okay. As long as the oil isn't filthy when you change it, the filter gets changed every time and you aren't using oil you should be fine.

No additives.
Follow Dodge's recommendations in the manual. They built it and they warranty it.

You could use the "severe service" guidelines because you are mostly towing.