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OCI, not when but why?


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13 minutes ago, diyer2 said:

I applaud Grumpy for his determination to fix this vehicle, I would have replaced it a long time ago.  

It depends. If it’s my wife’s go to town car, she likes to keep them. I’d just add oil and go. She’s never more than 9 miles away. Same with my go to town avalanche. My trip vehicles are usually on a short leash. First sign of trouble, gone. Standing on the side of the interstate. Not my idea of retirement activities. 

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If memory serves me right this is not a short trip car and to me doesn't matter. Besides I put up with or did a lot of things I didn't want to to save money or to pay the bills for years, now I'm on  the down side. Don't want to deal with it.

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3 minutes ago, diyer2 said:

If memory serves me right this is not a short trip car and to me doesn't matter. Besides I put up with or did a lot of things I didn't want to to save money or to pay the bills for years, now I'm on  the down side. Don't want to deal with it.

I hear you. The golden years are here. I do, drive, go where I want. But I believe Grumpy deal was I’m going to figure this out. Not a need to for economic situation. Otherwise add oil and go. Obviously spending more money than just adding oil. Hence my reason for the information.

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23 hours ago, KARNUT said:

I’m not being contrary. Maybe I missed something. Dizzy never got fixed? Is the conclusion that just adding oil after the initial damage was done. Would have been enough to make it last to the present mileage? What OCI would have overridden the bad design? If non. What would have been the life of the engine? Remember it’s been stated that 1000 miles per qt is normal. Normal mileage is still 15K miles a year. So 150K miles is 10 years. Most people move on from their daily by then. So how would you break it down under those parameters? What would be the recommendation for the average driver with a budget? Most people don’t change their own oil. 

 

Let's see if I can clarify this a bit. I understand it was a long journey.

 

Dizzy was motoring along just fine for years on 5K OCI's and QSUD and using nothing measurable during each. I'm not going to look up all the milage references, so these are 'out of hat'. About 80K is on the clock. 

 

Started using a little at this time and I just monitor. Not enough even to top off yet. At 100K a cam phaser gives up. Common problem with these units and as the issue was with the solenoid and not the actuator neither I nor my mechanic gave it a second thought. Starts using a bit more. 

 

Somewhere between 125 and 140K wife takes it on a 200-mile trip for work and it consumes like half a quart. That got my attention. Within the next change or two she gulped down a quart in 600 miles.

 

At 154K I call in the cavalry. I've switched to COSTCO oil as it is going through it so fast. First UOA shows 6.5% fuel, hi nitration and a viscosity break, high but in spec water but no damage seen. Fuel pump failures are rare in this motor so as the Nitration was high we started there. Plugs, coils, filters etc. Possible ring sticking? TRAX in an attempt to free them if they are indeed stuck and 40W oil to assist in the viscosity break if not.  

 

Next sample shows good improvement but damage. Rings stuck in most likely #1. 160K on the clock. I have RESTORE on hand but not enough to see it through a 30K regiment. So I Kreen the motor silly. 

 

167K sample shows rings free but still high fuels and water although the Nitration is under control now and the burn is clean. I attack the breather system. PVC replacing the CCV type. Oil consumption abates dramatically. Less than a quart in 10K?  

 

170K sample shows it got worse, 8% fuel but I have an idea that there is an issue with the tank venting system and replace it ALL but the tank proper. KREEN it again and change all the injectors. Move to 3K OCI's. 

 

173K best fuel to date, 5.0%, but still high and still breaking viscosity and consumption has increased again to a quart in roughly 5K. Reduce OCI to 2500 and replaced that fuel pump. Full Kreen on more time

 

178K Skipped a UAO while I ran two OCI's to purge the system of KREEN. BINGO 0.2% fuel and water is cut in half. Replaced plugs again. 

 

**********************************************************

 

I'm on 2,500-mile OCI's currently as she consumes about a quart in 5K and using Supertech, or COSTCO as the price would permit.

 

You can see for yourself the mistakes I made. Assuming pump condition. Assuming oil ability under those conditions. Assuming my nose was a good indicator of dilution. But I also had a hand in making those assumptions. GM didn't see it a problem. Failures are rare. Depending on the lab tech used for the OCI even the likelihood of the pump was always in question...until is was not and the last possible thing that could remotely have such an effect. Even pressure checks at the shop showed nothing abnormal in either pressures or fuel trims. Enough to be a problem and yet not enough to set off alarms. Crazy I know. 

 

Bottom line on usage is that at its worst it was a quart in 600 miles and now hovering a quart in 5,000K. So, is it fixed? By GM standards its stellar. By mine....it just as good as it is going to get and quite serviceable for a good long while yet.

Yes, I would call it a success. 

 

To your questions then 😉 

 

Given your parameters there are multiple possibilities for OCI. Two changes of 7.5K. (factory) Three changes of 5K. Five changes of 3K. Six at 2.5K. Seven at 2K. Fifteen at 1K. Every one of these has a follower. 

 

To me this has become a trust issue. You can follow the manufacture blindly and, in all likelihood, most will fare well doing so. That however is not trust. That is gullibility. I, personally, will have to have some assurance and I can only get that from data. Thing is, data by itself doesn't give you anything but numbers and while important to know what they ARE, it is more important to know what they MEAN. Therein "lies the rub" as the say. Labs all disagree, and I disagree with all labs. Oh, I agree on many, even most points but not ALL points. Thing is the few points I do disagree on are directionally inconsequential. That is the labs 'trigger point' is lower than my own. 

 

Let's get to the point, If I buy new, I will change early and often as I have always done, 500, 1,000, 2,500 at which point I take my first sample. I'm going to use the cheapest service I can find that will give me viscosity data and at least TBN. I will be consistent in my oil and filter, or this is useless. All I'm looking for at first is viscosity break and reserve alkalinity. I'm going to play the odds that with a new motor with a warranty that it will go 100K 😉 with just a little verification. I also want data on the unused oil. That one I spend money on. It's my touchstone. 

 

If those numbers look solidly in the middle at 2,500 I increase the OCI to 5K. Rinse and repeat until it is crowding the TBN. (50% fo the VOA ASTM4379). You will find this number depends on the unit, the oil and the service. 

 

Around 25,000 I pick a good lab and have a full workup done and I repeat this as often as the data suggest. That is, if it comes back perfect, I don't look again for about another 25K. That is unless I have a reason to belief something has happened. In your world that would be a look about every 18 months. 

 

Guess what I'm saying Stan is, I find the numbers that work for the motor, the oil and my service. Not one size fits all. In what limited data I have I have found RLHP to be good in Pepper for about 5K and RESTORE for perhaps 7.5K. Just can't find that anymore.

 

In DIZZY 5K was not quick enough but even given the pump issues 2K would have her to this day using zero oil. How long it took to break the viscosity at a slow fuel drip. 😬

 

IF the vehicle is used, I do a few quick changes and have a hard look. No idea what the guys who use motors for toilet paper have been doing, right? 

 

Hope this was helpful. It was for me to review this and spend a morning typing it up. Therapy let's call it. 😉 

 

 

 

 

 

 

 

 

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52 minutes ago, Grumpy Bear said:

 

Let's see if I can clarify this a bit. I understand it was a long journey.

 

Dizzy was motoring along just fine for years on 5K OCI's and QSUD and using nothing measurable during each. I'm not going to look up all the milage references, so these are 'out of hat'. About 80K is on the clock. 

 

Started using a little at this time and I just monitor. Not enough even to top off yet. At 100K a cam phaser gives up. Common problem with these units and as the issue was with the solenoid and not the actuator neither I nor my mechanic gave it a second thought. Starts using a bit more. 

 

Somewhere between 125 and 140K wife takes it on a 200-mile trip for work and it consumes like half a quart. That got my attention. Within the next change or two she gulped down a quart in 600 miles.

 

At 154K I call in the cavalry. I've switched to COSTCO oil as it is going through it so fast. First UOA shows 6.5% fuel, hi nitration and a viscosity break, high but in spec water but no damage seen. Fuel pump failures are rare in this motor so as the Nitration was high we started there. Plugs, coils, filters etc. Possible ring sticking? TRAX in an attempt to free them if they are indeed stuck and 40W oil to assist in the viscosity break if not.  

 

Next sample shows good improvement but damage. Rings stuck in most likely #1. 160K on the clock. I have RESTORE on hand but not enough to see it through a 30K regiment. So I Kreen the motor silly. 

 

167K sample shows rings free but still high fuels and water although the Nitration is under control now and the burn is clean. I attack the breather system. PVC replacing the CCV type. Oil consumption abates dramatically. Less than a quart in 10K?  

 

170K sample shows it got worse, 8% fuel but I have an idea that there is an issue with the tank venting system and replace it ALL but the tank proper. KREEN it again and change all the injectors. Move to 3K OCI's. 

 

173K best fuel to date, 5.0%, but still high and still breaking viscosity and consumption has increased again to a quart in roughly 5K. Reduce OCI to 2500 and replaced that fuel pump. Full Kreen on more time

 

178K Skipped a UAO while I ran two OCI's to purge the system of KREEN. BINGO 0.2% fuel and water is cut in half. Replaced plugs again. 

 

**********************************************************

 

I'm on 2,500-mile OCI's currently as she consumes about a quart in 5K and using Supertech, or COSTCO as the price would permit.

 

You can see for yourself the mistakes I made. Assuming pump condition. Assuming oil ability under those conditions. Assuming my nose was a good indicator of dilution. But I also had a hand in making those assumptions. GM didn't see it a problem. Failures are rare. Depending on the lab tech used for the OCI even the likelihood of the pump was always in question...until is was not and the last possible thing that could remotely have such an effect. Even pressure checks at the shop showed nothing abnormal in either pressures or fuel trims. Enough to be a problem and yet not enough to set off alarms. Crazy I know. 

 

Bottom line on usage is that at its worst it was a quart in 600 miles and now hovering a quart in 5,000K. So, is it fixed? By GM standards its stellar. By mine....it just as good as it is going to get and quite serviceable for a good long while yet.

Yes, I would call it a success. 

 

To your questions then 😉 

 

Given your parameters there are multiple possibilities for OCI. Two changes of 7.5K. (factory) Three changes of 5K. Five changes of 3K. Six at 2.5K. Seven at 2K. Fifteen at 1K. Every one of these has a follower. 

 

To me this has become a trust issue. You can follow the manufacture blindly and, in all likelihood, most will fare well doing so. That however is not trust. That is gullibility. I, personally, will have to have some assurance and I can only get that from data. Thing is, data by itself doesn't give you anything but numbers and while important to know what they ARE, it is more important to know what they MEAN. Therein "lies the rub" as the say. Labs all disagree, and I disagree with all labs. Oh, I agree on many, even most points but not ALL points. Thing is the few points I do disagree on are directionally inconsequential. That is the labs 'trigger point' is lower than my own. 

 

Let's get to the point, If I buy new, I will change early and often as I have always done, 500, 1,000, 2,500 at which point I take my first sample. I'm going to use the cheapest service I can find that will give me viscosity data and at least TBN. I will be consistent in my oil and filter, or this is useless. All I'm looking for at first is viscosity break and reserve alkalinity. I'm going to play the odds that with a new motor with a warranty that it will go 100K 😉 with just a little verification. I also want data on the unused oil. That one I spend money on. It's my touchstone. 

 

If those numbers look solidly in the middle at 2,500 I increase the OCI to 5K. Rinse and repeat until it is crowding the TBN. (50% fo the VOA ASTM4379). You will find this number depends on the unit, the oil and the service. 

 

Around 25,000 I pick a good lab and have a full workup done and I repeat this as often as the data suggest. That is, if it comes back perfect, I don't look again for about another 25K. That is unless I have a reason to belief something has happened. In your world that would be a look about every 18 months. 

 

Guess what I'm saying Stan is, I find the numbers that work for the motor, the oil and my service. Not one size fits all. In what limited data I have I have found RLHP to be good in Pepper for about 5K and RESTORE for perhaps 7.5K. Just can't find that anymore.

 

In DIZZY 5K was not quick enough but even given the pump issues 2K would have her to this day using zero oil. How long it took to break the viscosity at a slow fuel drip. 😬

 

IF the vehicle is used, I do a few quick changes and have a hard look. No idea what the guys who use motors for toilet paper have been doing, right? 

 

Hope this was helpful. It was for me to review this and spend a morning typing it up. Therapy let's call it. 😉 

 

 

 

 

 

 

 

 

I got what I was looking for. If the Honda is a DI motor I will shorten the OCI. It’s averaging 8K with the trips. My wife’s Genesis is a 4K the extreme schedule. The avalanche once a year as is the Acura. Thank you 

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21 hours ago, KARNUT said:

I got what I was looking for. If the Honda is a DI motor I will shorten the OCI. It’s averaging 8K with the trips. My wife’s Genesis is a 4K the extreme schedule. The avalanche once a year as is the Acura. Thank you 

 

Happy to accommodate and your welcome. My SPFI Asian motors go 7.5-8 with ease. Haven't owned a GDI Asian yet so I'll keep that in mind. Thanks! You have a nice day. I know this one is a busy on for you. Big family and all. 

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1 hour ago, Grumpy Bear said:

 

Happy to accommodate and your welcome. My SPFI Asian motors go 7.5-8 with ease. Haven't owned a GDI Asian yet so I'll keep that in mind. Thanks! You have a nice day. I know this one is a busy on for you. Big family and all. 

Yea 10 today, 15 or 20 Saturday. Smaller than years past. Kinda an every other thing. Seen as much as 40. My wife loves it. Me I rather do single family groups. I just smile and do the dishes and do the dishes and do more dishes. I keep the smile juice close and well stocked. This year flavored whisky neat.

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On 11/23/2022 at 12:02 PM, Grumpy Bear said:

To me this has become a trust issue. You can follow the manufacture blindly and, in all likelihood, most will fare well doing so. That however is not trust. That is gullibility. I, personally, will have to have some assurance and I can only get that from data.

Think this is the heart of the matter. As someone who often staked my faith in the manufacturer and their intervals, I’ve been on both sides of the issue.
 

But these days…when a manufacturer tells you who they are, you gotta believe them. Especially as we get pushed toward EVs. They have no reason to help you make your current vehicle last forever. The fox is guarding the henhouse.

 

When I bought my current truck I was immediately suspicious. It has a ZF transmission that’s used in a ton of applications. In those applications, ZF typically recommends transmission service at 60,000 miles or 8 years. But Ram? They say it’s lubricated for life.
 

If they mean for the life of the transmission, it becomes a self-fulfilling prophecy. Hell, everything can be “lubed for life” if you don’t expect it to last very long. If I never change the oil in my lawnmower and it blows up in 3 years, it was indeed lubed for life! Never mind that maintenance could extend said life by 10 fold.

 

More on point with engine OCIs…I did a UOA recently to gain some insight. By most measures my oil was spent. Yet the OLM indicated 34% life remaining, which could have amount to another 2k miles. Really?

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It never dawned on me that I live in a country so wealthy that even the poor look at a vehicle like they look at a toaster. Use it until it quits working and go buy another. The only difference between a poor person and the rich is how much they spend on it. 

 

Link below....

 

Changing components based on predicted life models is just a best guess. You need a condition based reliability approach to maintenance starting with oil analysis. - LEARN OIL ANALYSIS

 

 

Edited by Grumpy Bear
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5 hours ago, Grumpy Bear said:

 

 

It never dawned on me that I live in a country so wealthy that even the poor look at a vehicle like they look at a toaster. Use it until it quits working and go buy another. The only difference between a poor person and the rich is how much they spend on it. 

 

Link below....

 

Changing components based on predicted life models is just a best guess. You need a condition based reliability approach to maintenance starting with oil analysis. - LEARN OIL ANALYSIS

 

 

There’s several factors that determine life of a vehicle. In our business we’d change components by hours not failures during rain outs or seasonal downtime. There’re not making money broke down. Even changing oil was time consuming. That’s what lead us to Amsoil many years ago doubling hours between changes. Vehicles that were used for work were on a short lease usually traveling 50K miles a year. Usually 3 years was the maximum. If you’re traveling to a city to work everyday you want a dependable vehicle. Breaking down could cost you your life. If you live in the country with low travel roads and don’t venture far out. Any junk will do. My going to town vehicle is high mileage it doesn’t go far. I don’t drive it at night. My trip vehicle probably will never exceed 150K maximum. I’m not going to roll the dice. Same reason I don’t run my tires pass 50 percent wear. The wet traction is greatly reduced. When it comes down to it. I save money elsewhere. I like shiny new rides. And trying different vehicles. My research usually starts after a year. I got my eye on a couple. My daughters car is getting up in mileage. Hey you want a Honda? Next!

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1 hour ago, KARNUT said:

There’s several factors that determine life of a vehicle. In our business we’d change components by hours not failures during rain outs or seasonal downtime. There’re not making money broke down. Even changing oil was time consuming. That’s what lead us to Amsoil many years ago doubling hours between changes. Vehicles that were used for work were on a short lease usually traveling 50K miles a year. Usually 3 years was the maximum.

 

If I read this right, 150K was trade time; three-year lease at 50K a year? Statistically right on the money. :thumbs: 98% of vehicles will go 100K with zero maintenance but only 1.2% will go 200K even with normal scheduled maintenance.  

 

So, you changed parts based on 'hours'. Question, what were the number of hours based on? And why did you pick 2X on OCI instead of some other number? Why not 1.5X or 3X? 🤔 You don't seem the sort to take an arbitrary guess. 

 

Totally get the 'not making money broke down' thing and yes, for sure, safety. Absolutely.  

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32 minutes ago, Grumpy Bear said:

 

If I read this right, 150K was trade time; three-year lease at 50K a year? Statistically right on the money. :thumbs: 98% of vehicles will go 100K with zero maintenance but only 1.2% will go 200K even with normal scheduled maintenance.  

 

So, you changed parts based on 'hours'. Question, what were the number of hours based on? And why did you pick 2X on OCI instead of some other number? Why not 1.5X or 3X? 🤔 You don't seem the sort to take an arbitrary guess. 

 

Totally get the 'not making money broke down' thing and yes, for sure, safety. Absolutely.  

Amsoil recommendations. We were using conventional prior. Yes, they tested. My father had many years experience on wear and tear, he initially set the time line on maintaining. Break downs with equipment and trucks were rare. He was a hard sell on changing the OCI. Me to. Yup, me too. The equipment made quite a bit of money daily. Break downs were expensive. 

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On 11/13/2022 at 11:54 AM, customboss said:

Thats because TBN readings are testing for strong and weak acids in 2896. In 4739 is just strong acids.  Most additives packages, base oils,  have a baseline acid level that is inherent in the chemistry, not detrimental.  They aren't measurable accurately with a pat mathematical rule of thumb because the variables are so variable. 

 

For instance RLI BIOSYN base oils have a very high titration for acidity because of the nature of the HOBs baseoils.  

 

Estolides have a very low acidity because they are synthesized to some standard for that base oil need.  

 

Old school thought on TBN or BN was that it would neutralize all the bad acids but thats not true today in the world of high baseline or ambient acidity. Not necessarily bad acidity. 

 

For most modern engines your harmful acidity is coming from storing NOx's in the engine oil then refining it over and over via EGR effect.  

 

Traditional TBN will do nothing to counter that.  So having a targeted BN component is more important than raw measured titration #. 

 

You are correct Grumpy Bear to look at crossovers for your specific engine, with your specific fuels and oils in use, in your environment to see where wear and AN and BN crossover.  Having said that I can show you a HOBS based oil from RLI or Amsoil with their massively effective anti oxidants  that show near 0 TBN and stable acids with LOW wear.  

 

Oil blenders using 2896 method for TBN is a sales pitch to those who think higher is better.  With Mobil 1 ESP for instance the TBN might read 8 via 2896 and 6 via 4739 in clean oil but perform well from phenolic TBN boosters that won't show a high BN level.  

 

Chevron has released a HD diesel oil that has 0.4% sulfated ash ( a bench test to show ashy deposits formation tendencies) DELO 600.  Thats low enough to use in nat gas engines that have incredibly high nitration from high heat.  

 

That add pack made by Oronite is being incorporated into their passenger car/truck engine oils. 

 

Dexos1 Gen 2 requires less than at or lower than 1% SA.  Gen 3 requires max of 0.9%.  Why?  GM found that SA measured ash deposits will form in high heat areas like the ring belt, piston tops, turbo bearings, valves and valve guides and will visually look the same color as the alloys but harm compression and ESPECIALLY OIL CONTROL. 

 

NITRATION is the most important reading in our modern GM engines. Oxidation is NOT a player anymore. The base oils and additives are so good the oxidation rates are low no matter what.  DESIGN fuels dilution of the engine oil I THINK was used to cool the piston charge and lower NOx emissions but store the leftover NOx that sadly will be EGR'd into the oil again and the combustion chamber as deposits if a poor quality or inappropriate oil and fuels additives are in use.  

 

As diyer2 says most people don't care but if you have a problem baby that produces high heat you might want to use a better engine oil and best fuels you can get.  

 

I think the folks with the 6.6L V8 are seeing oil usage for the same reason I am in my L3B 2.7 T.  They are towing and producing high localized heating in the areas of engine described above.  I think I am too and I will be using a engine oil from Chevron Havoline 5w30 that is GEN2 Dexos1 that I know is 0.9% SA for sure to compare the consumption over time. 

 

API is slow on uptake here, DEXOS is faster to correct.  That above mentioned DELO 600 in a 10w30 or 5w30 would be interesting to see perform but its not optimized for fuel economy and friction reduction like the Havoline Pro-RS renewable I will be testing.  

 

Another note too, some oil makers that use very high quality base oils and additives advertise they meet and exceed DEXOS standards but if your engine eats that oil most likely it's not working that way, in my case a 2.7Turbo 4.  You can make ash deposits then clean them up with the solvency of the base oils or additives. When that solvency is diluted by fuel, EGR, and heat it might provide good wear control but you are consuming a qt of oil in 4000-7000 miles needlessly.  

 

 

 

So I've got a question.  Dexos 1 Gen 3 is approaching Dexos 2 levels of SA.  Dexos 2 oils (which are gas and diesel under 8600 GVWR spec) are SA of 0.8%.

 

2019 GM changed the LT1/LT4 Camaro/Corvette engines to run on Mobil 1 ESP Formula 0w40 which is a Dexos 2 spec oil.  Prior to this for track use they wanted the 5w30 Dexos 1 drained out, switch it to a 15w50 Mobil 1 for track use and then immediately drain that out and go back to the 5w30. 

 

They now spec the M1 ESP Formula 0w40 as an oil that can be used street and track and I assume that's because its low SA (and perhaps some other strengths to the additive blend?).  

 

So to my question, why not run a Dexos 2 spec oil in all the gas products?  Or more importantly, in their gas turbo products?  If SA is of concern and Dexos 1 G3 is now 0.1% off of Dexos 2 SA, why don't they just go full Dexos 2 spec?  Its a gas and diesel oil that's designed for emissions protection.

 

Here's a Dexos 1 chart I've found:

GM Dexos1 Gen 3 Engine Oil Specification | Chevron Oronite (Global)

 

adaptive_image_copy_copy_374807094.img.jpg

 

 

Here's a Dexos 2 spec chart I found:

GM dexos2 (lubrizol.com)

 

der.thumb.png.3cbd52f08197ed4a7693bec8e42f75ed.png

 

Edited by newdude
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