I hate the "Time Based" Oil Life Monitor
10-09-2018, 08:52 PM
#21
Le Mans Master
sounds like my fridge: the water filter is on a timer, regardless of use. and at least you can reset the car's OLM. the only way to reset my fridge is to buy another stupid RFID filter!
but i change 6qt in my truck every 5000mi, but the OLM flags every 3000mi. i just reset it & move on with my life.
the C5 gets changed around 10% unless i've done a lot of hard driving (or am about to after sitting for the winter).
but i change 6qt in my truck every 5000mi, but the OLM flags every 3000mi. i just reset it & move on with my life.
the C5 gets changed around 10% unless i've done a lot of hard driving (or am about to after sitting for the winter).
Last edited by _zebra; 10-09-2018 at 08:52 PM.
10-09-2018, 09:33 PM
#22
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sounds like my fridge: the water filter is on a timer, regardless of use. and at least you can reset the car's OLM. the only way to reset my fridge is to buy another stupid RFID filter!
i just reset it & move on with my life.
the C5 gets changed around 10% unless i've done a lot of hard driving (or am about to after sitting for the winter).
i just reset it & move on with my life.
the C5 gets changed around 10% unless i've done a lot of hard driving (or am about to after sitting for the winter).
I know why the fellow who used to post that worked with the GM PhD that developed the OLM after much testing and oil monitoring and chemical measurements STOPPED POSTING! In fact his posts were much much longer than mine and discussed in detail how the system worked. He said folks just ridiculed his comments!
Have no worry, I’ll never stop trying to post facts!
”The oil looks fine!!” Can you see sulfuric acid?
Last edited by JerryU; 10-09-2018 at 09:37 PM.
10-09-2018, 10:13 PM
#24
E-Ray, 3LZ, ZER, LIFT
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If in fact the C5 measured oil temp and time after a start the C7 no doubt does it better. It uses engine revolutions not just mileage that is a better indicator.
What it does that apparently gets some upset is it keeps track of time because folks did not do that or ever read the owner’s manual. It is much more complex than time and mileage. Have no idea where these ideas come from!
Can see why the fellow who worked for years developing the OLM with folks at GM making many chemical and wear measurements gave up posting! But don’t worry I won’t stop trying to shine a light on the subject! I post for the silent majority (now over 500 who have viewed this Thread) not the <15 folks who posted as I know I won’t or care about changing their minds since they “know” they are right!
Not trying to be insulting it’s just that some will believe the “Fake News” as it fits not wanting to do something they should! Your car do as you wish.
Last edited by JerryU; 10-09-2018 at 10:20 PM.
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BRussell (10-09-2018)
10-09-2018, 10:41 PM
#25
Le Mans Master
So I normally change my oil every year when I get my car inspected. And my car usually has 3500 to around 4500 miles per year at the time of inspection. As a comparison at that point my C6 would have said I had ~40 % or more life left. So this year at about an 11 month interval since the last change and 3000 miles driven, I'm down to 2% life left on the oil. That's absurd.
Of course, unlike many people, I actually drive both my C7 (about 25K a year) and the Ferrari (about 10K a year).
10-09-2018, 11:50 PM
#26
Le Mans Master
I like it a lot.
I drive my car year-round in almost daily use and keep the revs up more than the average driver. Thus, I know the OLM is clearly doing it's job well, because I'm generally only getting 5K miles between changes with the OLM winding down. That's about 5 months for me. I change it when it's approximately 20%.
Type of use and time are all important factors as to when a change is necessary for max engine protection and life, and the OLM algorithm does a terrific job of factoring all that in.
I drive my car year-round in almost daily use and keep the revs up more than the average driver. Thus, I know the OLM is clearly doing it's job well, because I'm generally only getting 5K miles between changes with the OLM winding down. That's about 5 months for me. I change it when it's approximately 20%.
Type of use and time are all important factors as to when a change is necessary for max engine protection and life, and the OLM algorithm does a terrific job of factoring all that in.
10-10-2018, 12:05 AM
#27
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Jerry,
You make a lot of good points. You said " Water is a combustion product. It mixes with sulfur and other “stuff” to form acids etc that cause corrosion. The OLM considers after each start how hot and how long the oil reaches temps that evaporate much of that water. It uses other factors, like engine revs etc as well."
The C6 did the same thing but left "time" out of the equation. I liked that system. Now take an unlikely scenario like suppose I put new oil in the engine on Day 1 and drove the car 30 miles and then parked it for another 364 days. The C7 would tell me I had to change the oil because it had 0% life remaining. That's bullshit. I would have liked a system that measured the things you mentioned that do degrade the oil and when a year came up even though the oil may have 40% life remaining (like my actual situation in my initial post where I only drove 3000 miles), it gave a message that said something like "Change oil because of 1 year limit". I like to know "why" I'm changing the oil. The C7 system fails in that respect. While I can't measure those characteristics that you mentioned that deteriorate the oil, an idiot can determine a year.
You make a lot of good points. You said " Water is a combustion product. It mixes with sulfur and other “stuff” to form acids etc that cause corrosion. The OLM considers after each start how hot and how long the oil reaches temps that evaporate much of that water. It uses other factors, like engine revs etc as well."
The C6 did the same thing but left "time" out of the equation. I liked that system. Now take an unlikely scenario like suppose I put new oil in the engine on Day 1 and drove the car 30 miles and then parked it for another 364 days. The C7 would tell me I had to change the oil because it had 0% life remaining. That's bullshit. I would have liked a system that measured the things you mentioned that do degrade the oil and when a year came up even though the oil may have 40% life remaining (like my actual situation in my initial post where I only drove 3000 miles), it gave a message that said something like "Change oil because of 1 year limit". I like to know "why" I'm changing the oil. The C7 system fails in that respect. While I can't measure those characteristics that you mentioned that deteriorate the oil, an idiot can determine a year.
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NSC5 (10-10-2018)
10-10-2018, 12:13 AM
#28
Anybody who still has a warranty( NOT ME!) would be foolish to ignore the OLM.
IF you ever would have an engine related failure, not being able to prove you complied with GM's requirements to do so, may be a deal-breaker.
Ignore at your own risk.
IF you ever would have an engine related failure, not being able to prove you complied with GM's requirements to do so, may be a deal-breaker.
Ignore at your own risk.
Last edited by owc6; 10-10-2018 at 07:58 AM.
10-10-2018, 12:37 AM
#29
E-Ray, 3LZ, ZER, LIFT
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Jerry,
You make a lot of good points. You said " Water is a combustion product. It mixes with sulfur and other “stuff” to form acids etc that cause corrosion. The OLM considers after each start how hot and how long the oil reaches temps that evaporate much of that water. It uses other factors, like engine revs etc as well."
The C6 did the same thing but left "time" out of the equation. I liked that system. Now take an unlikely scenario like suppose I put new oil in the engine on Day 1 and drove the car 30 miles and then parked it for another 364 days. The C7 would tell me I had to change the oil because it had 0% life remaining. That's bullshit. I would have liked a system that measured the things you mentioned that do degrade the oil and when a year came up even though the oil may have 40% life remaining (like my actual situation in my initial post where I only drove 3000 miles), it gave a message that said something like "Change oil because of 1 year limit". I like to know "why" I'm changing the oil. The C7 system fails in that respect. While I can't measure those characteristics that you mentioned that deteriorate the oil, an idiot can determine a year.
You make a lot of good points. You said " Water is a combustion product. It mixes with sulfur and other “stuff” to form acids etc that cause corrosion. The OLM considers after each start how hot and how long the oil reaches temps that evaporate much of that water. It uses other factors, like engine revs etc as well."
The C6 did the same thing but left "time" out of the equation. I liked that system. Now take an unlikely scenario like suppose I put new oil in the engine on Day 1 and drove the car 30 miles and then parked it for another 364 days. The C7 would tell me I had to change the oil because it had 0% life remaining. That's bullshit. I would have liked a system that measured the things you mentioned that do degrade the oil and when a year came up even though the oil may have 40% life remaining (like my actual situation in my initial post where I only drove 3000 miles), it gave a message that said something like "Change oil because of 1 year limit". I like to know "why" I'm changing the oil. The C7 system fails in that respect. While I can't measure those characteristics that you mentioned that deteriorate the oil, an idiot can determine a year.
Your hypothetical is unrealistic so why get your shorts in a knot with the possibility. In fact why are folks looking at the OL display much before a year or when it flashes as it gets close to time to change? You appear to agree with the change at one year but don’t like the intermediate percentages shown. I think some who drive few miles don’t understand that severe service includes short mileage drives that don’t get the oil hot and that corrosive oil NOT oil wearing out is a key reason to change! Probably better stated as the antiwear or acid neutralizing additives are depleted. Guess GM could state, “the oil acid neutralizing additives are no longer present to manage the sulfuric acid formed by excess blowby from all those starts you made without allowing the oil to ge hot enough, long enough,” but that would mean nothing to most folks!
Your car do as you wish, but as Lisa said after warranty as GM understands many folks don’t read the owner’s manual!
Last edited by JerryU; 10-10-2018 at 01:34 AM.
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Foosh (10-10-2018)
10-10-2018, 07:38 AM
#30
Melting Slicks
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Many good reasons to change oil by the monitor, most stated above.
But I think there's a human nature component to this dislike or distrust of the OLM. Consider this. Most of us have changed oil in our low mileage cars once a year, usually based on some annual activity that reminds us. Consciously, we know our oil is old and needs to be replace but we don't think of the oil as being at the end of it's life. That would imply we drove it yesterday on dead oil and that doesn't sit well in the owners mind, heck, it never crossed most owners minds. We don't tend to think this way. The oil is still good enough for a couple more months at least, right? NOW we have a computer that reminds us the oil is near the end of life. It's saying our oil is about dead and that contradicts the mental picture we've built and lived by. We tend to think of oil as a thing that has to wear out to reach end of life and our low mileage cars don't log that kind of mileage. We have to remember that the clock is ticking on our oil because the additives are being broken down, that's the trigger for end of life with modern oils.
I think the OLM is quite accurate. Its probably biased toward the safe side for GM's protection. If I were to build and warrant a high performance car that begs to be hammered on I'd bias my warrantee guide lines to my favor as well.
In the end, you can't change or turn off the OLM but you can reset it when it nags and it won't nag again for quite a while.
But I think there's a human nature component to this dislike or distrust of the OLM. Consider this. Most of us have changed oil in our low mileage cars once a year, usually based on some annual activity that reminds us. Consciously, we know our oil is old and needs to be replace but we don't think of the oil as being at the end of it's life. That would imply we drove it yesterday on dead oil and that doesn't sit well in the owners mind, heck, it never crossed most owners minds. We don't tend to think this way. The oil is still good enough for a couple more months at least, right? NOW we have a computer that reminds us the oil is near the end of life. It's saying our oil is about dead and that contradicts the mental picture we've built and lived by. We tend to think of oil as a thing that has to wear out to reach end of life and our low mileage cars don't log that kind of mileage. We have to remember that the clock is ticking on our oil because the additives are being broken down, that's the trigger for end of life with modern oils.
I think the OLM is quite accurate. Its probably biased toward the safe side for GM's protection. If I were to build and warrant a high performance car that begs to be hammered on I'd bias my warrantee guide lines to my favor as well.
In the end, you can't change or turn off the OLM but you can reset it when it nags and it won't nag again for quite a while.
10-10-2018, 07:52 AM
#31
Melting Slicks
If you could take the mileage out . What percent would the OLM drop each month if car just sat? My car is at 70 percent and will sit in storage for the next 5 1/2 months. What will my OLM percent be after storage?
Thinking of getting oil change now and get on a Oct / Nov oil change schedule. Low mileage car.
Thinking of getting oil change now and get on a Oct / Nov oil change schedule. Low mileage car.
10-10-2018, 08:10 AM
#32
E-Ray, 3LZ, ZER, LIFT
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…But I think there's a human nature component to this dislike or distrust of the OLM. Consider this. Most of us have changed oil in our low mileage cars once a year, usually based on some annual activity that reminds us. Consciously, we know our oil is old and needs to be replace but we don't think of the oil as being at the end of it's life.
…The oil is still good enough for a couple more months at least, right? NOW we have a computer that reminds us the oil is near the end of life. It's saying our oil is about dead and that contradicts the mental picture we've built and lived by. …We have to remember that the clock is ticking on our oil because the additives are being broken down, that's the trigger for end of life with modern oils.
I think the OLM is quite accurate. Its probably biased toward the safe side for GM's protection.
In the end, you can't change or turn off the OLM but you can reset it when it nags and it won't nag again for quite a while.
…The oil is still good enough for a couple more months at least, right? NOW we have a computer that reminds us the oil is near the end of life. It's saying our oil is about dead and that contradicts the mental picture we've built and lived by. …We have to remember that the clock is ticking on our oil because the additives are being broken down, that's the trigger for end of life with modern oils.
I think the OLM is quite accurate. Its probably biased toward the safe side for GM's protection.
In the end, you can't change or turn off the OLM but you can reset it when it nags and it won't nag again for quite a while.
Your car do whatever makes you happy but don’t ask GM to not tell you it should be changed to reduce your guilt!
10-10-2018, 09:38 AM
#33
Melting Slicks
I have no problem with the concept or workings of the OLM system. It does take into account the type of driving that has taken place. Last Summer we drove my wife's new Caddy XT5 to Texas, a 3,000 mile round trip. When we left home there were 1,200 miles on it and with 4,200 upon returning the OLM stil showed 70% remaining. She normally drives about 12,000/year so the oil change is only needed about every 9 months. We're leaving Monday for TX again and the F1 race in Austin. The OLM is at 50% now and I'll see what it shows when we return. Oil changes are free under the maintenance/warranty that's part of the ownership so no need to do it before down to 10% or so. Sure different from the every 3,000 miles that was the norm 20+ years ago...
10-10-2018, 09:55 AM
#34
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St. Jude Donor '16-'17,'22,'24
I’m sure you’re right for some folks it’s a psychological problem! Guess you could take a Valium or smoke a joint and just forget about it! Yep you can reset the OLM anytime you want and have it read what “makes you feel better!” But GM has worked hard to provide a device that does it’s best to indicate when to change oil. It is reported to be conservative so a few 1000 miles more won’t cause the engine to fall apart. But IF you use the Vette only occationally and for short trips the OLM with say change at fewer miles than you might “feel” are needed.
Your car do whatever makes you happy but don’t ask GM to not tell you it should be changed to reduce your guilt!
Completely agree. I really like the OLM setup. GM did a great job.
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JerryU (10-10-2018)
10-10-2018, 10:12 AM
#35
Race Director
If you could take the mileage out . What percent would the OLM drop each month if car just sat? My car is at 70 percent and will sit in storage for the next 5 1/2 months. What will my OLM percent be after storage?
Thinking of getting oil change now and get on a Oct / Nov oil change schedule. Low mileage car.
Thinking of getting oil change now and get on a Oct / Nov oil change schedule. Low mileage car.
Last edited by Patman; 10-10-2018 at 10:13 AM.
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Borntorun04/17 (10-10-2018)
10-10-2018, 10:34 AM
#36
The C7 is doing nothing different than my, ‘88, ‘93 and ‘2008 C6 said you need to do! It’s just measuring the time you were supposed to on your own! It does it because “the every idiot” you refer to does NOT read the service manual as evedenced by the many posts on this Thread!
Your hypothetical is unrealistic so why get your shorts in a knot with the possibility. In fact why are folks looking at the OL display much before a year or when it flashes as it gets close to time to change? You appear to agree with the change at one year but don’t like the intermediate percentages shown. I think some who drive few miles don’t understand that severe service includes short mileage drives that don’t get the oil hot and that corrosive oil NOT oil wearing out is a key reason to change! Probably better stated as the antiwear or acid neutralizing additives are depleted. Guess GM could state, “the oil acid neutralizing additives are no longer present to manage the sulfuric acid formed by excess blowby from all those starts you made without allowing the oil to ge hot enough, long enough,” but that would mean nothing to most folks!
Your car do as you wish, but as Lisa said after warranty as GM understands many folks don’t read the owner’s manual!
Excellent post, Jerry, particularly the part in bold above. After reading comments like "my oil looks fine," it's obvious why so many need systems like the OLM. It never ceases to amaze me on car forums how many completely uninformed folks think they somehow know better than experts. You can lead a horse to water, but you can't make him drink.
10-10-2018, 12:20 PM
#37
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SMH that so many people consider this a hot button issue. Changing oil is cheap, infrequent, and easy even if you want the dealer to do it. It's just not worth an argument. And remember the warranty issue.
As a young lad I was a 'boat puller' on an Alaskan troller. We fished for salmon along the Southeast coast. The owner of the boat insisted that "oil does not wear out!" and never changed the oil in his boat. Instead, he burned it. The amount of oil he poured into that engine on a weekly basis was enormous, but he considered it normal. The next season he had to replace his engine, a very expensive proposition on a boat like that.
As a young lad I was a 'boat puller' on an Alaskan troller. We fished for salmon along the Southeast coast. The owner of the boat insisted that "oil does not wear out!" and never changed the oil in his boat. Instead, he burned it. The amount of oil he poured into that engine on a weekly basis was enormous, but he considered it normal. The next season he had to replace his engine, a very expensive proposition on a boat like that.
10-10-2018, 12:47 PM
#38
Melting Slicks
My mileage dictates that I change the oil every year since I don't make the mileage requirement, as per the manual. I'll continue to do it that way until the drive train warranty is up, at which time I'll probably extend it somewhat. Since the car is not a DD I'll probably be averaging ~3k/year in the future and I wouldn't feel that using 5k regardless of time would be out of line. I don't do short trips that leave the oil below normal temperature and always warm the oil to at least 175° before shutting it down.
Last edited by iclick; 10-10-2018 at 12:49 PM.
10-10-2018, 01:02 PM
#39
SMH that so many people consider this a hot button issue. Changing oil is cheap, infrequent, and easy even if you want the dealer to do it. It's just not worth an argument. And remember the warranty issue.
As a young lad I was a 'boat puller' on an Alaskan troller. We fished for salmon along the Southeast coast. The owner of the boat insisted that "oil does not wear out!" and never changed the oil in his boat. Instead, he burned it. The amount of oil he poured into that engine on a weekly basis was enormous, but he considered it normal. The next season he had to replace his engine, a very expensive proposition on a boat like that.
As a young lad I was a 'boat puller' on an Alaskan troller. We fished for salmon along the Southeast coast. The owner of the boat insisted that "oil does not wear out!" and never changed the oil in his boat. Instead, he burned it. The amount of oil he poured into that engine on a weekly basis was enormous, but he considered it normal. The next season he had to replace his engine, a very expensive proposition on a boat like that.
I'm also amazed at many of the responses here.
Last edited by Foosh; 10-10-2018 at 01:05 PM.
10-10-2018, 05:52 PM
#40
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St. Jude Donor '13
If GM thinks that 364 days on the oil is ok but 366 days is too long, they should program the system to follow the old parameters and ignore the calendar until maybe the final week.
It seems like some people's driving habits have them paying the "penalty" for time and miles combined.
Not a problem for me at about 15k per year, two changes per year.
It seems like some people's driving habits have them paying the "penalty" for time and miles combined.
Not a problem for me at about 15k per year, two changes per year.
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Walt White Coupe (10-10-2018)