Read This if you have GM Oil Life Monitor

[Spector]

quote:

---

Originally posted by MNgopher:
[/qb]

---

Never mind those pesky UOA's that have shown many oils and engine combinations are not good past 3 or 4000 miles.

Well, this board has not really defined what is not good (plenty of opinions). Further, even if we thought that iron of 30 ppm and copper of 50 ppm were bad and a TBN of 1 the real issue (that no one has any concept of for a reply) is how long that engine would last given those wear numbers over its life.

So, we may think the UOA are poor but the real truth of how long the engine will last has never been answered. We need someone to go with the oil monitors the entire life of an engine and see what happens as compared to that same engien under similar conditions with the same oil changed at 3000 miles!

 

[Patman]

quote:

---

Originally posted by Spector:


Well, this board has not really defined what is not good (plenty of opinions). Further, even if we thought that iron of 30 ppm and copper of 50 ppm were bad and a TBN of 1 the real issue (that no one has any concept of for a reply) is how long that engine would last given those wear numbers over its life.

---

I was thinking about this today actually, that what would be really nice to see is someone who buys a car new, does UOA on every single oil change, and drives his car until his engine wears out. Then we could see just how the UOAs correlate into an engine's actual life. The only thing is, every engine will be different, so comparing a UOA on an iron block/iron heads V8 to an all aluminum 4 cylinder engine for instance, means almost nothing.

Sometimes we see a UOA and see 25-30ppm of iron in it and 15ppm of lead, and we think it's bad (I'm guilty of this too!) but who knows, that engine might still go 250k even with consistent UOAs like that. But even still, we strive to see the lowest wear numbers in our UOAs that we possibly can. It could be in vain though, seeing those super low numbers might mean our engine will last 400k vs 250k, but most people don't even keep their car to the 250k mark, so the extra engine wear reduction won't pay off for them.

I'll still continue my search for the holy grail though!

[ July 07, 2003, 03:49 PM: Message edited by: Patman ]

 

[Matt89]

What I wonder is, how precise are these tests for $20?

I'm thinking if you get a report that says 30 PPM iron, but the test is only accurate to plus or minus 20 PPM you haven't learned a whole lot...

There's a lot of parts in a million.

 

[unDummy]

TitaniumAlloy:
That million gallons of water saved only takes into account oil that is dumped in the yard/sewer.....
I'll still change my oil more often, not damage any water, and recycle all of my oil.

$5000 doesn't feed too many children when you consider all the administrative costs that these socalled nonprofit humane groups have. Screw those children, we'd be better off neutering the 3rd world to prevent all that child starvation.

And, we're not getting screwed by oil companies. We're getting screwed by politicians.
No matter what product you buy, you're taken for money. So, don't single out oil or gas companies.

No harm as long as you don't rev your engine all the time???? Ever hear of traffic, cold starts.....

Politics should be kept out of this forum.

 

[Calvin]

I have this GM Oil Life Monitor on my new Impala.There is no way on earth I am going to bother useing it.I am the exception.I have a sever driving pattern.I live 2 miles from work.The stores and shops I buy from a are within 1 to 5 miles.I bought the car in Fed 2003 and it's now July 2003 and I have a whopping 1,263 miles on it in approx 5 months of everyday driving.Of these only 200 or so miles was drivin on the freeways.So far during the breakin period I have changed the oil 4 times just to get the breakin wear metals out.Hopefully soon I can take it on a trip and get some freeway miles on as it needs them badly.Then maybe extend the OC miles to 1000 or so with dino oil.Friequent oil changes seem to be one of the few ways for me to protect the engine in my very sever service driving...I just cant imagine going a year between oil changes.But like I said I'm the exception.

 

[Titanium_Alloy]

Calvin, wouldn't be it easier for you just to walk to work? Just think about the benefits:

1. You don't spend any money on fuel
2. You don't have to do frequent oil changes; maybe twice a year would be enough. (But as I recall your manual recommend changing oil at least once a year)
3. You might not need the car at all - save your money on insurance, depreciation, interest paid, regular maintenance, and etc. If you really need a car once a week maybe you can rent it for $25 and don't have any worries.
4. Improve your health. Healthy steady walking and fresh air haven't harmed anyone.
5. Get all the money you saved and invest into your children educational fund. (If you don't have children, you might some day). Or get a good vacation for yourself.

[ July 07, 2003, 05:25 PM: Message edited by: Titanium_Alloy ]

 

[Calvin]

TA,

In theory you suggestion could happen.But the fact is that I am a caregiver.My elderly parents live(d) have lived with me for several years in my home.Due do mutipule dieses my father passed away late april and my mother (85) has Macular Degeneration and is legaly blind.For several years I have had to take them everywhere they needed to go as neither could drive.Due to the friequent doctor and hospitable visits and other trips , owning cars is simply a necessity.

 

[mph]

quote:

---

Originally posted by Matt89:
I'm thinking if you get a report that says 30 PPM iron, but the test is only accurate to plus or minus 20 PPM you haven't learned a whole lot...

---

It's not nearly that bad. I sent the same used oil to two labs, and the wear metals were mostly within 1 ppm. And 3 Mad Ponchos did an more thorough comparison.

You made a similar comment on the UOA thread from the Civic Si (Chevron Supreme vs M1) suggesting that the wear was similar, but I don't think that's true at all. It might well be due to break-in, rather than the oil, but the difference is there.

Was there something that gave you the idea that 20 ppm errors in wear metals were normal lab uncertainties?

 

[Titanium_Alloy]

Sorry, Calvin.
I didn't mean to offend you in any way.

 

[pscholte]

quote:

---

Originally posted by Patman:

quote:

---

Originally posted by Spector:


Well, this board has not really defined what is not good (plenty of opinions). Further, even if we thought that iron of 30 ppm and copper of 50 ppm were bad and a TBN of 1 the real issue (that no one has any concept of for a reply) is how long that engine would last given those wear numbers over its life.

---

I was thinking about this today actually, that what would be really nice to see is someone who buys a car new, does UOA on every single oil change, and drives his car until his engine wears out. Then we could see just how the UOAs correlate into an engine's actual life. The only thing is, every engine will be different, so comparing a UOA on an iron block/iron heads V8 to an all aluminum 4 cylinder engine for instance, means almost nothing.

Sometimes we see a UOA and see 25-30ppm of iron in it and 15ppm of lead, and we think it's bad (I'm guilty of this too!) but who knows, that engine might still go 250k even with consistent UOAs like that. But even still, we strive to see the lowest wear numbers in our UOAs that we possibly can. It could be in vain though, seeing those super low numbers might mean our engine will last 400k vs 250k, but most people don't even keep their car to the 250k mark, so the extra engine wear reduction won't pay off for them.

I'll still continue my search for the holy grail though!

---

Patman,

You're comments reignited

a thought I expressed in another thread on this board...
I wonder how well a chain of UOAs for an engine and an actual teardown of the same engine correlate.


--------------------------------------------------------------------------------

It would be nice to have a chain of UOAs for an engine and then have that engine torn down to see what correlation REALLY exists between the UOA results and what the engine ACTUALLY looks like inside. Some may say, "Well, duh, Scholte, it's a no brainer...good UOAs...clean engine with little or minimal wear when torn down," but have we actually seen some correlations from our own gang here on the site or cited elsewhere...you know, just as a confidence factor to show that what we believe "is what is." (Yes, I realize that what I pose means big big big bucks and that we are presently acting on the most logical info out there at a reasonable level of cost and effort, but still I wonder....)

 

[sbc350gearhead]

I change my oil on all my vehicles every 3000 miles, I always have and always will. If I didn't, I wouldn't have found out that my 99 toyota's head gasket was blown and leaking coolant into the oil as fast as I did at 40000 miles. I wouldn't have found out that it blew again at 60000 miles. I wouldn't have found out that the intake gasket was leaking on my old camaro, and was delivering fuel into my oil. To me....it's just making sure everything is fine with my engine.

 

[Calvin]

Titanium_ Alloy,

No offence taken.You couldnt possibly have known about this.No harm no foul.

 

[Matt89]

quote:

---

Was there something that gave you the idea that 20 ppm errors in wear metals were normal lab uncertainties?

---

mph;

No specific instances of problems with UOA...I was using those numbers (an exaggeration) just to illustrate a point that people are making some serious value judgments about the GM Oil Life System and many oils' performances without knowing 2 important pieces of data:

1) The margin of error in the UOAs.
2) How many PPM = dead engine.

How dumb would we feel to find out that the margin of error WAS as large as most of our metal readings, or that you could have 250 PPM of a given wear metal (iron or whatever) year after year and still get 200K out of the engine.

Without some idea of these two things, our interpretation of UOAs is at the mercy of:

a) The people at the labs, who have a vested interest in keeping us sensitive (perhaps overly so) to wear metals.

b) Comparisons to the standard 3000 mile interval, whose validity exists in tradition and habit.

No offense to Terry or any other "analyzer"...I think it's fair to look critically at anyone's perspective when they get paid $ for anything automotive. If people should question the motives of the oil companies and carmakers, they should also question the labs.

I hope that I added to the discussion and not sidetracked it...

[ July 07, 2003, 08:26 PM: Message edited by: Matt89 ]

 

[turbochem]

quote:

---

I change my oil on all my vehicles every 3000 miles, I always have and always will. If I didn't, I wouldn't have found out that my 99 toyota's head gasket was blown and leaking coolant into the oil as fast as I did at 40000 miles. I wouldn't have found out that it blew again at 60000 miles. I wouldn't have found out that the intake gasket was leaking on my old camaro, and was delivering fuel into my oil. To me....it's just making sure everything is fine with my engine.

---

Or you could have done some UOA's while extending your drains..........

I think the only way this issue will be settled, is to get someone with an oil monitor to do a couple of UOA's when the engine tells him to.........

Anything outside of that is pretty much just speculation.

I think I'll change my intervals to 500 miles (is that too high?)...can't be too careful!!!

 

[Titanium_Alloy]

It's kind of interesting that people don't trust GM. GM is a huge car manufacturer with dozens of research labs and hundreds of specialists. They test and retest each car and engine multiple times. They track all dealership records and customer complains. They monitor all government statistics and I hope they are trying to improve their cars (as well as any other car maker).
I wonder if people who own BMW, Mercedes, and Porsche also don't trust their maintenance systems. I believe recommended oil change in BMW something around 15000 miles or 2 years, in Porsche GT3 it's 12000 miles. Please note that both brands are considered sporty and driven pretty hard (especially Porsche). Yet we see claims from oil change places and people 3000 miles! 3000 miles! 3000 miles!

This info is taken from Porsche GT3 website:

"Longer service intervals not only contribute to a more intelligent use of materials and resources, they also help to minimize maintenance costs. On the new 911 GT3, we've reduced servicing requirements to a minimum: engine oil every 12,000 miles, oil filter and air filter every 24,000 miles, spark plugs every 24,000 miles or four years, and fuel filter every 48,000 miles. Better still, the original coolant charge is good for the life of the car."

Note that oil filter needs to be changed every 24000 miles.

Another point about wear metals. Take for example Pontiac Grand AM 3.4 V6 oil capacity 4.5 quarts. BMW 525 and 530 inline 6 oil capacity 6.9 quarts. Difference of almost 2.5 quarts. Make both cars run 10000 miles on the same oil in the same manner. Don't you think that BMW will have less wear numbers because of larger oil dilution?

 

[mph]

quote:

---

Originally posted by Titanium_Alloy:

I wonder if people who own BMW, Mercedes, and Porsche also don't trust their maintenance systems. I believe recommended oil change in BMW something around 15000 miles or 2 years, in Porsche GT3 it's 12000 miles.

---

But don't they also have more stringent oil specifications than GM? (Aside, perhaps, from the Corvette.)

 

[Titanium_Alloy]

mpg:
You're absolutely right. However, all those brands don't have the same oil monitor. Each brand has its own minimum oil specifications as well. I believe (but don't know for sure) that oil monitor is configured differently not only for specific car brand, but for each car engine and car type. Let's say LS1 Corvette engine will probably have a different oil monitor algorithm compared to LS1 Camaro engine because Corvette requires synthetic oil and Camaro doesn't. Also Corvette engine operates at 220F and Camaro at 210F; I suppose it also makes a difference.
I don't think that BMW 330 has the same oil monitor algorithm as BMW M3 (which practically has the same engine, but with a bigger bore). It also has different oil requirement as well.
I think that car manufacturers take into consideration minimal oil requirements (and not the best oil available for the car) when designing oil monitor so they can be on the safe side.

[ July 08, 2003, 12:01 AM: Message edited by: Titanium_Alloy ]

 

[CJH]

quote:

---

Originally posted by davefr:
I have one of these oil life monitors in my GTP. I have zero confidence in GM's algorithm.

---

[/QB][/QUOTE]

What amazes me about so many people thinking GM is incompetent in recommending oil change intervals is that they have 100% confidence in recommending the oil grade. It seems like everyone on here says "I only use the grade the manufacturer recommends" while at the same time saying "I have zero confidence in recommended oil change intervals. I am going to disregard their recommendations and change it more frequently."

If GM is so smart about picking the right oil grade, why are they so incompetent about setting the oil change intervals? I don't agree with this thinking. I think you are just reluctant to accept change and clinging onto your old familiar ways.

 

[Whimsey]

Just curious. But has anyone who has these oil life monitors, especially GM's, since most of their vehicles spec in dino oil, done a UOA of the oil that was in the vehicle when the reminder light came on. Especially with the initial factory oil. It would be interesting to see the condition the oil was in. And just because you change your oil on a regular basis does not mean that you are environmentally insensitive. Why I don't dump the used oil in the lake across the street from me, I first put it in the plastic bottles and sink them into the lake! The plastic containers shouldn't deteriorate for decades.

, JUST KIDDING! I really take the oil to the local recycling center.

Whimsey

 

[3 Mad Ponchos]

quote:

---

What I wonder is, how precise are these tests for $20?

---

Here is your answer:
http://neptune.spacebears.com/cars/stories/margins.html
MOST elements are plus or minus 5 ppm or less, though a few are higher. Flashpoint is the worst, it's so imprecise as to be almost unusable.

For those wondering about a UOA after the oil light comes on, the oil light came on 52 miles after the 5k sample in my study. So look at the 5k numbers and there you go. Of course, that is synthetic oil, not dino juice.

Cheers, 3MP