How long is too long for oil, time wise?

[austai]

It's 15 months since I put in synthetic and only 5K miles have been travelled. 5K miles is nothing for a synthetic in a non-turbo'ed car, but 15 months seems kinda long. Should I change it anyway? I'm thinking of going to a good GF-4 oil henceforth and changing every 12 months.

Good plan?

 

[pitzel]

How does 40 years or more sound?

Thats how long we left initial fills of oil in some of our equipment at my former place of employment. UOA's kept coming back just fine.

 

[Bryanccfshr]

It depends on how those miles are accomplished. If those 5k miles are from short trips then it is probably too long. If it is from nothing but highway trips and never get's pulled out of the garage for anything but a good long drive then I think time matters much less, especially with a quality sytnetic. I would be using Lube Control regardless.

 

[austai]

The trips in the car were always long enough for the car to reach operating temperature, though usually under 4 miles - the distance from my house to work.

 

[pitzel]

My suggestion then would be to give it a good hour long drive on the highway ASAP, pull a UOA sample, send it in, post here, and you will have a pretty good idea of how the engine oil is doing under your conditions.

Make sure your testing lab performs a TBN titration. Once you know how the oil is standing up to your service over this interval, it should be pretty straightforward to adjust your oil change interval to ensure lubricant is most effectively used.

 

[Gene K]

I would review the 6 year / 8800 mi Porsche Boxster run on factory fill in the UOA section.
1 year OCI may be a safeguard but this UOA convinced me they are not a absolute requirement.

I seriously doubt 4 mi was enough to get the oil up to operating temperature 200&#176F+. Do you have a oil temperature gauge?

Gene

 

[Quattro Pete]

quote:

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Originally posted by Gene K:
I seriously doubt 4 mi was enough to get the oil up to operating temperature 200

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Exactly. 4 mi may be enough to get the coolant temp up to normal (which is what the gauge on the dashboard shows in most cars) but not the oil.

During winter, in my A4 it takes 3-4 miles to get the coolant up to normal temp, but it takes 8-10 miles to get the oil up to normal temp. Granted, my winters are a bit colder than those in Texas, but nevertheless, you get the point.

As for the original question, do a UOA and find out for yourself if 15 months is too long based on your engine and your driving patterns. For me, after 12 months (and about 5K miles) I already managed to accumulate 1% fuel in my oil because of the way I drive, hence I will not push it past that. You can see my UOA in the archives. On the other hand, there's that brilliant Boxster UOA which Gene K mentioned, and that's why I say, you can only find out what's right for you by doing a UOA because there's no universal answer.

 

[austai]

quote:

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Originally posted by Gene K:

I seriously doubt 4 mi was enough to get the oil up to operating temperature 200&#176F+. Do you have a oil temperature gauge?

Gene

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No, just have a water temp guage, but it reaches normal operating temp within 1.5-2 miles of starting off. FWIW, I'm in central Texas where it's mild or warm most of the year, if not outright hot. Also, the car has a manual transmission and once the water temp reads normal, I'm not reluctant to rev it hard. The RPM is usually AT LEAST 3-5K when the car isn't stopped.

That Boxster results do make me feel better.

 

[John_E]

When my Passat 1.8T developed an internal cam seal leak, my cam chain adjuster would not start to clatter until after at least 20-30 minutes of driving, which is when I assume the oil had finally reached its full operating temperature. The coolant temperature came up to its normal operating value, 190F, within the first 2 miles. Based on this, I don't think 4 miles of driving is enough to warm the oil sufficiently to boil out the sludge-promoting, engine-damaging moisture. When I drove 5K miles or less per year, I kept my cars on a strict 3-month OCI, which I relaxed gradually over the years to 6 months, as oil additives improved. Short trips are murder on internal combustion engines.

 

[ekpolk]

quote:

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Originally posted by pitzel:
How does 40 years or more sound?

Thats how long we left initial fills of oil in some of our equipment at my former place of employment. UOA's kept coming back just fine.

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Pitzel: You've made a couple similar statements here before. I'm not at all disputing the correctness of the statement, but this is the second time I've asked: what type of equipment are you talking about????

 

[pitzel]

quote:

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Originally posted by ekpolk:

quote:

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Originally posted by pitzel:
How does 40 years or more sound?

Thats how long we left initial fills of oil in some of our equipment at my former place of employment. UOA's kept coming back just fine.

---

Pitzel: You've made a couple similar statements here before. I'm not at all disputing the correctness of the statement, but this is the second time I've asked: what type of equipment are you talking about????

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Electrical transformers anywhere from 200kVA to several hundred MVA, 4.16kV all the way up to 230kV.

While electrical transformers do not experience the effects of combustion byproducts, the point I am making is that oil just sitting in an enclosure literally doing nothing will not be subject to break-down. Only actual use of the machinery and the addition of combustion byproducts contributes to lubrication degradation.

Not referring to any of the special chlorinated oils either. Just straight mineral Voltesso, which, other than good dielectric strength, isn't anything special.

[ January 01, 2005, 12:42 AM: Message edited by: pitzel ]