ZDP depletion and GM oil life monitor

[Patman]

Keep in mind that the factory setups for a lot of things are not always the best possible choice, but are a compromise, due to budget constraints, fuel economy regulations, etc. So the tire choice for any given car is not guaranteed to be the 100% best choice, and each individual who owns the car will have different priorities there too (some might want best tread life, some might want best rain performance, others might just want max handling potential)

In terms of the factory programming, that is not going to give you max power either, nor will it always give you max fuel economy. They set it up very conservatively so that the engine does not destroy itself the first time you drive it up a steep hill in 100 degree weather. So the fuel mixture is going to be set richer than optimum.

This is why taking your car to a performance shop and getting them to dyno tune it based on your exact setup is going to be much more precise than a factory calibration which is identical for all cars.

The same goes for oil choice. I for one do not believe Mobil 1 5w30 is the best choice in the LS1 family of GM engines. I base this on seeing a good number of oil analysis reports on here which show higher wear compared to when someone tries out an oil more on the thicker side of the 30wt range. Since Mobil 1 5w30 is only 10cst, it only has an HTHS of 3.0 to 3.1, while the oils closer to 12cst, with HTHS numbers of 3.5 to 3.6, have shown lower wear in oil analysis.

GM chose Mobil 1 5w30 for the Corvette for a number of reasons, one of them being availability. You can find it everywhere! I'm also sure they've got a nice deal going with Exxon/Mobil too, something that the smaller oil companies couldn't compete with. Mobil 1 also has a big presence in the "synthetic world", the average person who knows virtually nothing about oil has still probably heard the name Mobil 1.

So along comes people like us here on BITOG, who aren't satisfied just using an oil that is good, but want something that is great! Will Mobil 1 5w30 get you 250k out of your Corvette engine? Most likely, so long as you drive it relatively gentle. But what if you're like me, and like to go drag racing once a month, and like to go full throttle a lot on the street? I doubt I'd get 250k out of my engine in that case. But by choosing an oil with a higher HTHS, one which shows much lower engine wear in oil analysis, I believe I do have a very good shot at going beyond 250k on the original LS1 engine in my 98 Corvette.

Just one more quick point. Mobil 1 5w30 tends to show higher oil consumption in the LS1 compared to German Castrol 0w30 (which is 12.2 cst at 100c, vs 10.0 for M1) as well. Many people I talk to from both LS2.com and LS1Tech.com who have taken my advice and switched their LS1 engines over to GC 0w30 from M1 5w30 come back to tell me later that their oil consumption improved dramatically. This is another good reason for switching!

 

[Gary Allan]

quote:

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Fleets or test cars are running with the production intent designs and lubes on accelerated durability, endurance, emissions, track testing, etc... The products are testing far in excess of what any customer can do.

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(let's take a different approach here)

In your experience ..what happens when an incidence of failure occurs in a given component or system during this testing. Is it necessarily remied ...or does a cost/benefit/risk analysis take precedence over a finer, more durable, product/component/system if it deemed to be too far below some preset likelyhood of failure above XX% in production models???

 

[buster]

quote:

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Keep in mind that the factory setups for a lot of things are not always the best possible choice

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True. With Mobil 1, it has to meet a set criteria. Price, availability, protection, API formulation, fuel economy etc. On BITOG, we go strictly for protection.

I would say though that Mobil 1 does well in LS1's. We see higher wear metals, but nothing too significant IMO. And I don't think Amsoil has proven to be any better at all. Only German Castrol has really done well. If I had a Vette, it would get Redline or Fuchs/Silkolene.

 

[Patman]

quote:

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Originally posted by Gary Allan:

quote:

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Fleets or test cars are running with the production intent designs and lubes on accelerated durability, endurance, emissions, track testing, etc... The products are testing far in excess of what any customer can do.

---

(let's take a different approach here)

In your experience ..what happens when an incidence of failure occurs in a given component or system during this testing. Is it necessarily remied ...or does a cost/benefit/risk analysis take precedence over a finer, more durable, product/component/system if it deemed to be too far below some preset likelyhood of failure above XX% in production models???

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Two of my cousin's work for GM, one of which is an engine test engineer at the LS1/LS2/LS6 assembly plant in St.Catharines Ontario. He tells me that a lot of times GM knows that they could get a longer life out of a component if they switched to something else, but the beancounters will often put the stop to it. Something as simple as a ten cent per engine increase in price might seem insignificant to us, but multiply it by the number of engines GM produces and the beancounters just don't want to invest that much, even though it'll cost them more in the end, due to the warranty claims!

But in a big dinosaur like GM, one department doesn't really care if it costs another department more money, they just worry about their own bottom line. They don't look at the bigger picture. It's crazy!

 

[jason07-1zzfe]

Excellent question Gary

 

[TomJones76]

quote:

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Originally posted by Patman:
SNIP
But in a big dinosaur like GM, one department doesn't really care if it costs another department more money, they just worry about their own bottom line. They don't look at the bigger picture. It's crazy!

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Speaking as an employee of a Fortune 1000 high technology manufacturing firm, this problem is not confined to GM.
I routinely see marketing's needs squash engineering's goals.
I routinely see accounting squash engineering's goals.
I routinely see marketing's needs squash service's goals.
I routinely see accounting squash service's goals.
As an aside, bbobynski, thanks a ton for coming over here and posting. Your comments are eye-opening.

 

[Donald]

Two questions, 1) do various oils have different amounts of ZDP. Better/synthetic have more? Not sure the oil company specs list ZDP content. 2) How can one extend oil change in a car without GM Oil Monitor and still be confident that there is a sufficient quantity of ZDP. Oil analysis does not pick up ZDP level explicitly, so many gauge it by TBN, which may not match ZDP depletion in same linear fashion.

 

[nickmckinney]

quote:

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Originally posted by Jason Troxell:

quote:

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Originally posted by bbobynski:
...My same comment applies....how do those darned Powertrain engineers manage to design/develop/validate an engine like the Corvette LS6 and not know the proper oil viscosity for it....LOL LOL Use the recommended viscosity. That is what the engine runs all validatin and endurance testing with. If you use something else YOU are doing the testing.

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Don't know. How did they manage to design/develop/validate the intakes and intake gaskets on most V6 and vortec V8's that have been leaking coolant internally for 10yrs?

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Yeah and Ford SCREWED up with the plastic coolant crossover on the 4.6 intake, and Mopar SCREWED up with the sheet metal plenum intake cover on the Magnum engines (I own one of each of above myself)

This is sounding like a witch hunt or a place to vent all frustrations about everything else other than the topic "ZDP depletion and GM oil life monitor"

Alot of you folks sound like a bunch of whiny school kids! You FINALLY get a GM engineer in here to give some perspective from the OEM side of oil issues, and now everything that GM ever did wrong he gets questioned for?!?!

Hello but GM like every other OEM has to make the same car work EVERYWHERE with EVERYONE doing EVERYTHING they can think of, and they need to do it at a price SOMEONE will pay. Will mistakes be made along the way? H-e-l-l ya they will, thats all a part of life. IMHO - the only perfect car ever made was a 427 Cobra, anything else, just a compromise. So please folks, lets get back to our regularly scheduled program "ZDP depletion and GM oil life monitor"

 

[bbobynski]

quote:

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Originally posted by Gary Allan:

quote:

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Fleets or test cars are running with the production intent designs and lubes on accelerated durability, endurance, emissions, track testing, etc... The products are testing far in excess of what any customer can do.

---

(let's take a different approach here)

In your experience ..what happens when an incidence of failure occurs in a given component or system during this testing. Is it necessarily remied ...or does a cost/benefit/risk analysis take precedence over a finer, more durable, product/component/system if it deemed to be too far below some preset likelyhood of failure above XX% in production models???

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In my experience in a lot of years and a lot of engine programs I have never seen a problem "overlooked" due to cost, timing, or anything else. If there is a failure during testing, it is root caused and the cause addressed....period. I have NEVER seen cost raised as a reason NOT to fix a problem recognized. The difficulty with any engine, or especially a completely new design, is to accelerate all the durability and endurance testing so as to recognize any shortcomings of the design/materials/engineering without introducing failures purely because of "over testing". For instance, to accelerate fatigue testing on the lower end of the engine it is run wide open at max output, max RPM for hundreds of hours...something that no customer could ever do even on the autobahn. Trying to make the determination between harsh enough to accelerate the testing without causing failures purely due to the test is a challenge. Father time is also difficult to hurry.....which is a big factor in corrosion and corrosion induced problems.

 

[bbobynski]

quote:

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Originally posted by Patman:

quote:

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Originally posted by Gary Allan:

quote:

---

Fleets or test cars are running with the production intent designs and lubes on accelerated durability, endurance, emissions, track testing, etc... The products are testing far in excess of what any customer can do.

---

(let's take a different approach here)

In your experience ..what happens when an incidence of failure occurs in a given component or system during this testing. Is it necessarily remied ...or does a cost/benefit/risk analysis take precedence over a finer, more durable, product/component/system if it deemed to be too far below some preset likelyhood of failure above XX% in production models???

---

Two of my cousin's work for GM, one of which is an engine test engineer at the LS1/LS2/LS6 assembly plant in St.Catharines Ontario. He tells me that a lot of times GM knows that they could get a longer life out of a component if they switched to something else, but the beancounters will often put the stop to it. Something as simple as a ten cent per engine increase in price might seem insignificant to us, but multiply it by the number of engines GM produces and the beancounters just don't want to invest that much, even though it'll cost them more in the end, due to the warranty claims!

But in a big dinosaur like GM, one department doesn't really care if it costs another department more money, they just worry about their own bottom line. They don't look at the bigger picture. It's crazy!

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Nonsense. First, there is no engine development done at St Cats so any "testing" is purely hot testing production engines. St Cats is a manufacturing facility only...not an engine development site. I do not understand how any decisions about costs or potential changes or failures are going to be determined there. It just doesn't happen that way. People might see things happen and theorize what is going on but the engineering decisions and the cost and engineering discussions take place well away from St Cats so I would not expect dyno operators there to be in on the discussions.

Be carefull of feedback from techs running dyno test stands. They have a very biased view of the world that is a product of their environment....LOL... EVERY test that they run on an engine is designed to stress it to the limit, accelerate wear and fatigue and flat out break things in the process....soooo...all they see is torn up engines. That is by design and is the nature of the testing. If an engine runs wide open/full power for 300 hours and meets our bogey for high speed endurance then it "passes". Sometimes we tear it down for evalution. Sometimes it continues on test for another 100 hours. If it blows up in the process, the tech thinks "another failed engine...they ALL fail...so this engine must be the cheapest POS around..." I hear this all the time from dyno techs, garage techs, etc.... They do not stop to realize that the purpose of the testing is often to creat broken parts...or that the strenous nature of the testing turns the slightest problem into a mess of parts on the floor. So take their input with a large grain of salt.

I have personally NEVER seen a failure root cause overlooked because of timing, cost or anything else. It is addressed if there is failure. Product engineering has an equal say in design/material/part changes with the "bean counters" and they cannot be overruled by the bean counters. In fact....I haven't seen many "bean counters" around any of the engineering reviews and parts release discussions in a long time....LOL

[ April 20, 2005, 05:32 PM: Message edited by: bbobynski ]

 

[mettech]

BB

What about fuel?... What type/brand of gas do you use for testing? I use Shell or Chevron only
because it's a Top Tier gas.

What say you?.. lol

I would also like to thank you for the time and information you have put in on several diffrent boards. You might be the best advertisment that GM has!!!!lol

 

[bbobynski]

quote:

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Originally posted by Donald:
Two questions, 1) do various oils have different amounts of ZDP. Better/synthetic have more? Not sure the oil company specs list ZDP content. 2) How can one extend oil change in a car without GM Oil Monitor and still be confident that there is a sufficient quantity of ZDP. Oil analysis does not pick up ZDP level explicitly, so many gauge it by TBN, which may not match ZDP depletion in same linear fashion.

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Yes, different oils have different levels of ZDP. The "gasoline" engine oils that are rated with the starburst GF4 symbol would typically have the lower amounts of ZDP I would say as there is a concerted effort to reduce ZDP levels in oils where it is not required to minimize possible poisoning of the catalytic converter. Not to say that there isn't plenty of anti-wear additive in those oils...just that the concentration is probably lower there than in some other oils.

I think that the ZDP level of the oil is very important and is one of the major gauges of how "worn out" the oil is. It is hard to get good analysis of ZDP concentration in oil so I suspect that is why the TBN becomes the criteria that people fixate upon since it is readily avaialable. The TBN is certainly important...but it is only ONE factor in determining the oil life and lesser in importance than some other things in my opinion and it does not correlate to the ZDP depletion from what I have seen.

You have hit on why the oil life monitor is such a good thing. Before the oil life monitor was developed and the research done with oil analysis to back up the performance and accuracy of the oil life monitor, there was really no way to determine accurately how to extend the oil life and everyone asked the same question you just did....the answer is the oil life monitor. Since it is always monitoring the conditions and accounting for the factors that deteriorate the oil it is by far the most accurate method of doing this.

Which is why I am so critical at times of the extended change intervals marketed by some oil brands. Without taking all the factors into account you cannot reliably extend the oil change interval without taking some risk. Even the oil life monitor has built in safety factors to always err on the side of changing the oil too soon if need be.

The ultimate setup will be the oil life monitor in conjunction with an oil quality sensor in the oil pan. With these two pieces of data the oil life monitor can be used without the severe safety factors to dramatically extend the oil change intervals with little or no additional risk of "over-extending" it. Since it will be able to compare and cross check with the condition sensor the system will be much smarter and will really be what is required to dramatically extend the oil change intervals beyond what they are today.... That system was what was demonstrated on the technology demonstrator STS that was shown at the recent SAE show in Detroit.

 

[Ugly3]

quote:

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Originally posted by bbobynski:

I have personally NEVER seen a failure root cause overlooked because of timing, cost or anything else. It is addressed if there is failure. Product engineering has an equal say in design/material/part changes with the "bean counters" and they cannot be overruled by the bean counters. In fact....I haven't seen many "bean counters" around any of the engineering reviews and parts release discussions in a long time....LOL

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No, no, no. You have to blame big bad "bean counters" for the POS products coming out of industry because if the decisions were up to the Engineers no product would ever fail. It must be the bad "bean counters" who cause all the problems.

On a serious note, I have been in industry for 40 years and my experience is similar to yours. Sure the bean counters say some project has a poor return or there are not enough resources to do something, however, I have never seen a beancounter spec a part for a product or demand that some manufacturing process be altered.

The truth will prevail.

 

[bbobynski]

quote:

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Originally posted by mettech:
BB

What about fuel?... What type/brand of gas do you use for testing? I use Shell or Chevron only
because it's a Top Tier gas.

What say you?.. lol

I would also like to thank you for the time and information you have put in on several diffrent boards. You might be the best advertisment that GM has!!!!lol

---

I think most any of the major brands is a sure bet... I tend to gravitate toward Mobil from past experience. Even when other gas companies were shirking on the anti-deposit additives years ago (that led to a lot of the injector plugging and driveability issues with PFI) Mobil kept them in the fuel despite the cost disadvantage to them.

You are always at the mercy of the station operator as they can dump anything into their tanks....but the majors police this to some extent as they do have more at stake.

Understand that within a given geographic area all the gas for most all the stations comes from just one or two terminals so the different tankers are filling up at the same spot from the same source....just the additive packages in the fuel is what is distinguishes the different brands in many cases.

 

[CONMCK]

Please...NOT ALL ENGINES ARE THE SAME. The example above is an excellent practical justification of why you would want to add EOS and change the 15W40 Delvac in the muscle car at 3000 miles max and yet can run the Northstar to 12500 easily on conventional oil. You must treat each engine and situation differently and what applies to one does not retroactively apply to others. This is where Amsoil falls short in my book by proposing long change intervals in most everything if you use their oil. It just doesn't work that way. You can run the Amsoil to 12500 with no concerns whatsoever in the late model Northstar because even the oil life monitor tells you that for conventional oil off the shelf. Would I do that to the 502 in my 66 Chevelle...NO WAY. Amsoil says I can though. Wrong.
Question for bbobynski:

In your first post you use an example of 15w-40 Delvac with some EOS added, would this be what you would recommend for a high horsepower street strip engine SBChev making 1.1-1.2hpower/cu in. Or what would you recommend based on your expertise?

 

[Doug Hillary]

Hi,
an interesting thread

I was trained (Engineering) by BMC in NZ and in England during the 1950-60s
The demise of the British Motor Industry was mainly capital and labour based. At the Engineering level many vehicles - cars, heavy trucks, buses - were produced with significant defects that in those years had a lead time to rectification/production that was measured in years! This was before computors and "clean" lines of communication of course

In BMC's case (Leyland and etc. included)the defects were in engines, gearboxes (Minis, Minore etc),cooling systems, body design (cooling etc), suspension/steering and many more areas. In Leylands case I have worked with Engineers that have cried because no money was available to develop/refine their excellent engine designs that were already in production and causing user strife. Leyland's diesel engines were admired worldwide during the 1940-1960 period. They were watching and participating in their own demise

My last contact at an Engineering level in England was in 1975 - and things had NOT changed in nearly 20 years

Exit the British Motor Industry

Regards
Doug

 

[oilyriser]

What data does the OLM require? Can an OLM be designed that we could buy, and attach to our non-GM cars? Maybe a small magnetic pickup could be placed over a fuel injector, and it would monitor fuel usage, and engine revolutions. A temperature probe could be included, to see if it is a cold or a warm start.

You'd need to do some oil analysis to calibrate the unit, but maybe a good guess could be made, just using TBN.

 

[BenDarDunDat]

quote:

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Originally posted by oilyriser:
What data does the OLM require? Can an OLM be designed that we could buy, and attach to our non-GM cars? Maybe a small magnetic pickup could be placed over a fuel injector, and it would monitor fuel usage, and engine revolutions. A temperature probe could be included, to see if it is a cold or a warm start.

You'd need to do some oil analysis to calibrate the unit, but maybe a good guess could be made, just using TBN.

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In the mid to late 90's, BMW used an OLM that used input from multiple sources: RPM, coolant temps, # cold starts, etc.,etc. In the late 90's they changed to a system that only monitors the fuel quantity comsumed. They claim the results are comparable with the more complex algorythm.

 

[Doug Hillary]

Hi,
BenDarDunDat - sorry but my BMW has the original system and the newer system is much more sophisticated as I understand it
The oil change interval is now centered around 25k kms up from the 15k kms previously used

Fuel use is pobably one of the best ways to estimate oil life but it tells nothing about the oil's CONDITION! UOAs are advisable if using this method.
Fuel and hours are used in the Earthmoving and Marine Industries amongst others

Regards
Doug

 

[427Z06]

quote:

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Originally posted by Ugly3:
No, no, no. You have to blame big bad "bean counters" for the POS products coming out of industry because if the decisions were up to the Engineers no product would ever fail. It must be the bad "bean counters" who cause all the problems.

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Wow! Upper management never overuled a proposed solution to a remedy a product shortcoming due to costs in the world you lived in? I never had an opportunity to work as an engineer at one of those places.