GM Offers Oil Life Monitor Information

[ABN_CBT_ENGR]

When I asked on Mopar app this is what I was told. The system checks oil with electric single as this determines oil condition, rpm, start cycle, ethanol content, outside temp, engine temp, mileage of engine, load of engine as well as overall health of engine. What this tells me is since they can check condition of oil then Synthetic oil will cause light to come on later as it flows better. He called it flex which is based off Mercedes Benz system.

And sadly, all of them are just educated guesses based on lab tests on a lab engine taken from instrumentation where accuracy and calibration is not known or verified and based on an equation measured against an engineered performance number.

None of which is even remotely assured to be an accurate representation of the condition of "your" oil in "your" engine.

Just saying to keep it real.

 

[4WD]

I ask because my local GM dealer has ACDelco full synthetic 0w-20 in the shop and listed in their system as the "OEM fill" for a particular 2020 vehicle. The manual states to use a synthetic 0w-20, 5w-20, 0w-30, or 5w-30. However, the OEM has to know that 90% of people that buy a new car may flip through the manual only to figure out how to work the new radio, and then it gets tossed in the glove box never to be opened again. Some of those same people are cheap in that they'll want the

Because I was stuck out of town early this year … had to get oil changed at a Jiffy … they told me the lowest cost oil that carries GM approval was Pennzoil Gold … (this sounded like his standard pitch) so I went with that … I’m sure others do as well. To be honest, this store was honest and he showed me that my air filter was actually still good etc … So I had the oil changed and car vacuumed etc … No up sales …
Being in a small college town probably meant you had a manager and university students …

 

[BryanTDI12]

For those asking about an OLM that would coincide with other services, Honda has a good OLM imho. It will pop up with a combination number 1-6, each number corresponding do a different service item.
#1 is always oil change,
#2 is engine and cabin filter,
#3 transmission fluid,
#4 spark plugs and timing belt,
#5 coolant, #6 rear diff
Prefixes A and B means the car needs an inspection and oil filter change or not.
Ex. A16 would tell me oil (no filter) and rear diff fluid change only. B1 is oil+filter+inspection of suspension/cv boots/etc.

From my understanding, each item has a coded max mileage limit and the computer will decide to flex the service to the closest oil change. Trans fluid gets replaced near 30k miles but if the OLM detects the engine oil is nearing the end of life, it will flex the trans fluid to be changed at 27k miles to coincide with the engine oil change.

The only catch is you have to run the OLM down to 15% or below. It will not show the service items until then. if you reset the OLM early at say 50%, it will assume you already did the items it predicted but you have no idea what it wanted. I see this all the time on the Honda Pilot forums I frequent. "I never had the trans fluid code in all the 80k miles I've driven. When do I change it?" Stop resetting the OLM early. What's annoying too are the dealer maintenance packages for 30/60/90k miles trying to lump together all the services and put 5k mile oil sticker on the windshields completely circumventing Honda's OLM.

I do like Honda's OLM and wish more manufactures would adopt a similar way. I've programmed my VWs for flexible service instead of the default 10k miles and adjusted the limits from the default 30k miles/ 2 years to now 10k miles/1 year but I have to keep track of other service items.

 

[Hall]

Well, they do, just not directly. If you count revolutions, you'll get half the number of combustion events (4 stoke engine). At idle, you'll be counting revolutions at idle speed, say 700 per minute. At 5,000 RPM, you'll count 5,000 per minute. So it decreases oil life much faster at higher RPM than it does at low RPM.

What I meant was they don't (directly ?) correlate high RPM operation as being harder on an engine.

 

[Snagglefoot]

The OLM is really more for telling air head owners that maybe they should change their oil. We Bitoggers take it too literally that we need to work with it.

 

[slacktide_bitog]

Wow, GM actually uses mileage now? The earlier GM OLM cars specifically said that mileage is not accounted at all by the system!

2013 is when they started going heavy on the TGDI, so it makes sense to limit to 7500 miles. Going to zero as soon as it overheats is a good idea. I hope they also implemented something on the other end, for example, only short trips and the engine never warms up to operating temp.

The European OLM cars like Mercedes go by how much fuel is used. I'm surprised GM didn't implement this.

 

[ABN_CBT_ENGR]

What I meant was they don't (directly ?) correlate high RPM operation as being harder on an engine.

Speaking in generic general terms as a design engineer ( but never worked on an OLM project), I would almost guarantee you not.

The reason is most likely because in "design terms" the stress analysis is at least 2 phases.

The baseline is the properties of materials ( velocity, expansion, stretch, deformation and all that plus thermal) - in that realm the RPM is accounted for by the set redline measurement by design.

The 2nd phase is more dynamic and is where the properties designed against in phase 1 are measured against load ( resistance and torque). That's what "harder" really represents against the stress and strain curves- not how fast but how fast against what force pushing back.

That's a lot of calculating and instrumentation.

That's just a guess but again, I doubt they go that far into the weeds.

 

[tiger862]

And sadly, all of them are just educated guesses based on lab tests on a lab engine taken from instrumentation where accuracy and calibration is not known or verified and based on an equation measured against an engineered performance number.

None of which is even remotely assured to be an accurate representation of the condition of "your" oil in "your" engine.

Just saying to keep it real.

Lol We would hope it wasn't just a guess. Millions of people rely on the system to be accurate as well as test in real world have been sent in to places such as Blackstone which claim life is still left in oil. Do I wish I wouldn't have to look at manual for tire rotation or filter change sure but at least I don't have to remember oil changes. I rotate my tires at 6k but never know if or when time to replace other than looking at them. I am not worrying about replacing tires on the oil change schedule as it is a separate service. Air filter is 30k or time and cabin filter another but there are others as well so I look at manual when oil change is done to check items coming up on recommended changes


2018 Grand Caravan
18000 miles

 

[JohnnyG]

When I asked on Mopar app this is what I was told. The system checks oil with electric single as this determines oil condition, rpm, start cycle, ethanol content, outside temp, engine temp, mileage of engine, load of engine as well as overall health of engine. What this tells me is since they can check condition of oil then Synthetic oil will cause light to come on later as it flows better. He called it flex which is based off Mercedes Benz system.

This is ALMOST Total BS!
No way an "electrical signal" can test the condition of your motor oil, let alone "Load of the engine", and don't get me started on "overall health of the engine". And "flows better" really, meaning it's sheared out of grade?
Yeah, based off of Mercedes system for emptying your wallet!

 

[UncleDave]

I'll put up the latest OLMs against anyones intuition on the matter.

While certainly not perfect a few of them have been highly tuned and worked on

Hondas, and the GM's latest LV v8 code are two of the more mature higher versioned examples that have had reliable testing against their predictions.

There is a lot of information that can be inferred and reliably calculated from analyzing a variety of operational info that is captured.

Take a look at a high level brief of Hondas for example...



UD

 

[4WD]

This is ALMOST Total BS!
No way an "electrical signal" can test the condition of your motor oil, let alone "Load of the engine", and don't get me started on "overall health of the engine". And "flows better" really, meaning it's sheared out of grade?
Yeah, based off of Mercedes system for emptying your wallet!

Hate to hear an OLM empties wallets …
… they are what moved me from 5,000 to 7,500-10,000 mile OCI’s

 

[tiger862]

This is ALMOST Total BS!
No way an "electrical signal" can test the condition of your motor oil, let alone "Load of the engine", and don't get me started on "overall health of the engine". And "flows better" really, meaning it's sheared out of grade?
Yeah, based off of Mercedes system for emptying your wallet!

It is a dielectric sensor that reads amount and type of contaminants in the oil, as well as how the vehicle is being driven. All they have to do monitor throttle for load then use other sensors for overall health. If check engine light is on shortened oil change, lots of fuel used over shortened interval, shorter oil change, high idle time, shortened oil change etc
It even shortens for ethanol
Is it perfect I would say no. Like I said it is based on Mercedes Benz Flex Service System and most that drive Mercedes never do there own maintenance and rely on vehicle to tell them when oil change is needed.

 

[blingo]

A few details on Hella's old combination sensors: https://www.ama-science.org/proceedings/getFile/AGRl

 

[ABN_CBT_ENGR]

It is a dielectric sensor that reads amount and type of contaminants in the oil, as well as how the vehicle is being driven. All they have to do monitor throttle for load then use other sensors for overall health. If check engine light is on shortened oil change, lots of fuel used over shortened interval, shorter oil change, high idle time, shortened oil change etc
It even shortens for ethanol
Is it perfect I would say no. Like I said it is based on Mercedes Benz Flex Service System and most that drive Mercedes never do there own maintenance and rely on vehicle to tell them when oil change is needed.

With all due respect, I would like to know the name of this sensor, manufacturer and proof that it can do all of this from a single point reading.

No such device exists and anyone who believes otherwise needs to set one on the table where I can send it to Emerson for analysis.

 

[ABN_CBT_ENGR]

I'll put up the latest OLMs against anyones intuition on the matter.

While certainly not perfect a few of them have been highly tuned and worked on

Hondas, and the GM's latest LV v8 code are two of the more mature higher versioned examples that have had reliable testing against their predictions.

There is a lot of information that can be inferred and reliably calculated from analyzing a variety of operational info that is captured.

Take a look at a high level brief of Hondas for example...

UD

That's just another way of politely promoting a WAG by trying to convince people its a SWAG but all roads end at unqualified guess based on indirect data that in no way can be correlated to actual conditions.

 

[ABN_CBT_ENGR]

Lol We would hope it wasn't just a guess. Millions of people rely on the system to be accurate as well as test in real world have been sent in to places such as Blackstone which claim life is still left in oil.

Respectfully,

"Hope' is not a strategy nor is it a proper vetting authority and "random coincidence" that it can match another test with a vague generality is not proof of anything- much less establishing validity of something that by its very nature cannot be considered a direct measurement of a product.

 

[tiger862]

With all due respect, I would like to know the name of this sensor, manufacturer and proof that it can do all of this from a single point reading.

No such device exists and anyone who believes otherwise needs to set one on the table where I can send it to Emerson for analysite

No More Guesswork Mercedes-Benz sensor tells when to change oil

The new Mercedes-Benz 3.2L V-6 can do many things very well. Among them: taking the M-Class sport/utility vehicle (SUV) up steep and rocky inclines and speeding the new CLK coupe effortlessly along the autobahn.It can also tell a driver when it's time for an oil change.The three-valve per...

www.wardsauto.com

 

[tiger862]

No More Guesswork Mercedes-Benz sensor tells when to change oil

The new Mercedes-Benz 3.2L V-6 can do many things very well. Among them: taking the M-Class sport/utility vehicle (SUV) up steep and rocky inclines and speeding the new CLK coupe effortlessly along the autobahn.It can also tell a driver when it's time for an oil change.The three-valve per...

www.wardsauto.com

This is an article from 98

 

[ABN_CBT_ENGR]

That's old news. That's advertising hype.

Those are simply old PH type meters. They don't "measure" anything- they flag on a value (PH, conductivity, acid etc..

Highly inaccurate and very unreliable.

 

[tiger862]

Respectfully,

"Hope' is not a strategy nor is it a proper vetting authority and "random coincidence" that it can match another test with a vague generality is not proof of anything- much less establishing validity of something that by its very nature cannot be considered a direct measurement of a product.

I am glad you know the meaning of what hope is. There are many people "hope" their situation gets better.