Oil Consumption

[asilverblazer]

22 hours ago, riddler said:

1 qt per 3k miles?

Give or take, all but my earliest vehicles had that short an interval. To be sure any vehicle I've touched this century, generally they've all been on a minimum 5k interval.

[asilverblazer]

6 hours ago, KARNUT said:

At least in my case according to the manufacturer’s oil measuring device my vehicles worked as designed.

To be clear I'm not arguing whether your vehicles do or do not use oil. I am interested in continuing a technical discussion about what amount, if any, we can measure as being 'used' or 'lost'.

 

As I stated, I measure the oil volume that I have drained from the oil pan and compare that directly to how much I put back in. There is always more going in than what came out. Generally, at a minimum, 1-2 cups, at most 1-1.5 quarts. The smaller discrepancies, were smaller oil capacity engines (5 quart load) and the larger discrepancies were on larger oil capacity engines (9 quarts). 

 

Generally, these never showed any 'measurable' oil loss per the dipstick(s). Oil was always within the marked area. Could it have been higher in the marked area one time vs another, I have to assume so, but the level on the stick never warranted a more significant dipstick reading accuracy check. 

 

I've come to the conclusion that so long as the oil level is within the range on the dipstick the volume is acceptable. Any loss that doesn't exceed the published acceptable use or fall below the dipstick marking is not considered a problem, meaning, the amount that I see being lost are not 'abnormal' or enough to warrant further investigation. 

 

Could it be that your measurement method isn't accurate enough to show an amount of oil loss? (This isn't an insult; I am exploring the measurement limitations of dipstick readings.) 

 

To wit, an oil pan that spreads a large volume over a greater surface area compared to a narrower pan would show variations in their measured volume quite differently on a dipstick.

[KARNUT]

41 minutes ago, asilverblazer said:

To be clear I'm not arguing whether your vehicles do or do not use oil. I am interested in continuing a technical discussion about what amount, if any, we can measure as being 'used' or 'lost'.

 

As I stated, I measure the oil volume that I have drained from the oil pan and compare that directly to how much I put back in. There is always more going in than what came out. Generally, at a minimum, 1-2 cups, at most 1-1.5 quarts. The smaller discrepancies, were smaller oil capacity engines (5 quart load) and the larger discrepancies were on larger oil capacity engines (9 quarts). 

 

Generally, these never showed any 'measurable' oil loss per the dipstick(s). Oil was always within the marked area. Could it have been higher in the marked area one time vs another, I have to assume so, but the level on the stick never warranted a more significant dipstick reading accuracy check. 

 

I've come to the conclusion that so long as the oil level is within the range on the dipstick the volume is acceptable. Any loss that doesn't exceed the published acceptable use or fall below the dipstick marking is not considered a problem, meaning, the amount that I see being lost are not 'abnormal' or enough to warrant further investigation. 

 

Could it be that your measurement method isn't accurate enough to show an amount of oil loss? (This isn't an insult; I am exploring the measurement limitations of dipstick readings.) 

 

To wit, an oil pan that spreads a large volume over a greater surface area compared to a narrower pan would show variations in their measured volume quite differently on a dipstick.

Don’t get hung up over this. No disrespect intended. People have a different opinion of what constitutes using oil. I stated mine. 

[riddler]

7 minutes ago, KARNUT said:

Don’t get hung up over this. No disrespect intended. People have a different opinion of what constitutes using oil. I stated mine. 

Doesnt take an engineer to read a dipstick. Otherwise the manufacturer would require dealership oil level checks. Not brain surgery either. 

[Atlas]

Ok well I guess Lake disagrees with me on a few points.

• I call oil consumption pretty basic. Rudimentary. He calls it "really complicated."
• I think 1qt consumed in 3k miles is a lot. He says that's normal.

In 22 minutes, he'll use his natural talent to explain oil consumption to anyone watching this video. He covers everything from obvious engine damage to how normally functioning healthy engines consume oil by design.

• Lake explicitly states how you drive will impact oil consumption.

 

Shut up and watch:

 

 

[riddler]

I dont care what Lake says. Goodnight. 

[Chuck FB]

5 hours ago, Atlas said:

Ok well I guess Lake disagrees with me on a few points.

• I call oil consumption pretty basic. Rudimentary. He calls it "really complicated."
• I think 1qt consumed in 3k miles is a lot. He says that's normal.

In 22 minutes, he'll use his natural talent to explain oil consumption to anyone watching this video. He covers everything from obvious engine damage to how normally functioning healthy engines consume oil by design.

• Lake explicitly states how you drive will impact oil consumption.

 

Shut up and watch:

 

 

 

There are a few good takeaways in that video that pertain to this thread, certainly the possibility of the oil control rings having buildup, the fuel injectors and how clean or not that they are ending up affecting the pistons rings carbon buildup, and the fact that its normal up to a point for a given engine to use some oil, and that the oil quality that is being utilized is part of that ring clogging up issue as well.

 

I was talking with a neighbor yesterday who has a baby LZ0 duramax and he had bought it slightly used but it does consume some oil and he has switched over to 5W-30 Euro spec oil and in this case that never made a difference in consumption over the factory 0W-20 recommendation. He finds it uses a quart in about 3500 miles and as he goes a ways over that distance he adds oil to full and goes another 1000 miles or so and then changes oil and is typically at 40% or so left on the oil monitor at that point with his use case of quite a lot of highway miles and more limited in short run use. I don't know what other LZ0 engines are doing for oil consumption but that is what his is doing. 

[KARNUT]

No I didn’t watch a video of a person who analyzes oil for a living explain general oil usage. For clarity I did ask my brothers one who runs our equipment business. The other who runs our old ROW business about oil usage. Nothing has changed since I retired. Their personal vehicles or work vehicles use no oil. Not enough to see on the oil checking device. Then I pondered. I like to ponder. In this extended oil changing world with oil change countdowns or lights. If engines used say a qt every 2500 miles or up to even 4000 miles. With oil changes reaching as high as 15000 miles. Normal for most people is eight to ten. Vehicles should potentially be seizing up all over the place. Especially in hilly terrain. Just how many people actually check their oil? Maybe 10 percent. Those are the people that probably change their oil early. I like to research used car listings. I have five favorite dealers I check. They all list carfax with their listing. It’s rare to see vehicles with anything but extended oil changes. Transmission service, forget about it. I’ve seen Honda and Toyota certified vehicles up to 100K miles and ten years old. With nothing but normal maintenance. Isn’t nice we all have different experiences and believe our way is the best. You certainly get backup for whatever you believe. Life would be boring otherwise.

[Atlas]

2 hours ago, KARNUT said:

No I didn’t watch a video of a person who analyzes oil for a living explain general oil usage. For clarity I did ask my brothers one who runs our equipment business. The other who runs our old ROW business about oil usage. Nothing has changed since I retired. Their personal vehicles or work vehicles use no oil. Not enough to see on the oil checking device. Then I pondered. I like to ponder. In this extended oil changing world with oil change countdowns or lights. If engines used say a qt every 2500 miles or up to even 4000 miles. With oil changes reaching as high as 15000 miles. Normal for most people is eight to ten. Vehicles should potentially be seizing up all over the place. Especially in hilly terrain. Just how many people actually check their oil? Maybe 10 percent. Those are the people that probably change their oil early. I like to research used car listings. I have five favorite dealers I check. They all list carfax with their listing. It’s rare to see vehicles with anything but extended oil changes. Transmission service, forget about it. I’ve seen Honda and Toyota certified vehicles up to 100K miles and ten years old. With nothing but normal maintenance. Isn’t nice we all have different experiences and believe our way is the best. You certainly get backup for whatever you believe. Life would be boring otherwise.

 

You appeared to be fixated on the idea that an engine that "uses" oil only uses a copious and highly noticeable amount between changes, otherwise it uses absolutely nothing. Your assumption is wrong yet you keep trying to prove it by...asking your brothers? Who's trying to keep up with their siblings now?!

 

Trace amounts are still consumed during combustion and through other engineered designs like PCV... whether you like it, or think it's true, or not.

 

Go ahead, keep doubling down, and proving to us all that you're incapable of having an intelligent discussion about engines on a truck forum.

 

Hint: It's not your experience that's wrong, it's how you express it and what you believe it means. There's a difference.

[Atlas]

5 hours ago, Chuck FB said:

 

There are a few good takeaways in that video that pertain to this thread, certainly the possibility of the oil control rings having buildup, the fuel injectors and how clean or not that they are ending up affecting the pistons rings carbon buildup, and the fact that its normal up to a point for a given engine to use some oil, and that the oil quality that is being utilized is part of that ring clogging up issue as well.

 

I was talking with a neighbor yesterday who has a baby LZ0 duramax and he had bought it slightly used but it does consume some oil and he has switched over to 5W-30 Euro spec oil and in this case that never made a difference in consumption over the factory 0W-20 recommendation. He finds it uses a quart in about 3500 miles and as he goes a ways over that distance he adds oil to full and goes another 1000 miles or so and then changes oil and is typically at 40% or so left on the oil monitor at that point with his use case of quite a lot of highway miles and more limited in short run use. I don't know what other LZ0 engines are doing for oil consumption but that is what his is doing. 

 

I've got just under 3k on my LZ0 and it's hard to tell what it's doing because I changed the oil at 500, 1500, and getting ready to do it again. The next interval will span 2k miles before probably going to a max of 3500 -- but using the recommended 0w20. Some superstition, and some data, I don't want to do longer intervals for the real or perceived possibility of the oil losing viscosity with longer use, starting from only 20 weight oil. I use Mobil 1 ESPx2.

 

In the last 1500 miles most of it has been higher speed, highway driving 70mph+, and only a little towing. I topped off the oil at about 2750 miles, adding about 1/8 quart to put the level back on full. IMO, nothing to worry about.

 

There's still a possibility a defective thrust bearing could take out the whole engine before 10k or so. That's a lovely thought to ponder, but if it happens, I'll get the engine replaced and send the truck down the road and find something else.

[KARNUT]

33 minutes ago, Atlas said:

 

You appeared to be fixated on the idea that an engine that "uses" oil only uses a copious and highly noticeable amount between changes, otherwise it uses absolutely nothing. Your assumption is wrong yet you keep trying to prove it by...asking your brothers? Who's trying to keep up with their siblings now?!

 

Trace amounts are still consumed during combustion and through other engineered designs like PCV... whether you like it, or think it's true, or not.

 

Go ahead, keep doubling down, and proving to us all that you're incapable of having an intelligent discussion about engines on a truck forum.

 

Hint: It's not your experience that's wrong, it's how you express it and what you believe it means. There's a difference.

Being they have access to hundreds of trucks and equipment like I do. Their input would seem worthy. Not everyone lives in a small little world. Like it appears you do.

[Chuck FB]

12 minutes ago, Atlas said:

 

I've got just under 3k on my LZ0 and it's hard to tell what it's doing because I changed the oil at 500, 1500, and getting ready to do it again. The next interval will span 2k miles before probably going to a max of 3500 -- but using the recommended 0w20. Some superstition, and some data, I don't want to do longer intervals for the real or perceived possibility of the oil losing viscosity with longer use, starting from only 20 weight oil. I use Mobil 1 ESPx2.

 

In the last 1500 miles most of it has been higher speed, highway driving 70mph+, and only a little towing. I topped off the oil at about 2750 miles, adding about 1/8 quart to put the level back on full. IMO, nothing to worry about.

 

There's still a possibility a defective thrust bearing could take out the whole engine before 10k or so. That's a lovely thought to ponder, but if it happens, I'll get the engine replaced and send the truck down the road and find something else.

 

I know the claim was that they overfill the LZ0 or unless it was the first series of 3.0 duramax an additional quart due to more oil use before the rings/cylinder mates together. My neighbors is a refresh 2022 model and who knows what changes they could have made between then and now and no two engines are exactly alike and it would probably have some bearing on how the engine was broken in and serviced as well. 

 

I'd be doing exactly like you are, a few short interval oil changes ( not sure if you cut open the filters, you might not want to know what was inside of them ! ) and shorter intervals over all for oil changes and you've more than done your part. If it piles up, that's completely on GM and its there baby to cover the cost of a new engine. 

 

By the way the neighbor said he just had that coolant diverter contraption replaced on is truck, don't recall the miles that is on his truck now but certainly within the warranty period yet and so was all covered as he said there was a time when they were not covering that under the power train warranty but now they are as I believe he would be over the bumper to bumper warranty in distance I believe and certainly past in the three year time frame. 

[GAMark]

On 5/29/2026 at 4:40 PM, riddler said:

You have been weighed, measured and found wanting.  According to GM it is normal. So you disagree with your brand, finally got to the place of sanity. You have serious insecurity issues. .probably stems from neglect from childhood, or improper weening from the milk teat.

 

Always one JA on every forum.

You have been weighed, measured, and found wanting ( A Knight's Tale)!

Edited 1 hour ago by GAMark

[KARNUT]

If a tree falls in a forest does it make a sound? If you don’t add oil between oil changes. Does it use oil? 

[Atlas]

12 minutes ago, Chuck FB said:

 

I know the claim was that they overfill the LZ0 or unless it was the first series of 3.0 duramax an additional quart due to more oil use before the rings/cylinder mates together. My neighbors is a refresh 2022 model and who knows what changes they could have made between then and now and no two engines are exactly alike and it would probably have some bearing on how the engine was broken in and serviced as well. 

 

I'd be doing exactly like you are, a few short interval oil changes ( not sure if you cut open the filters, you might not want to know what was inside of them ! ) and shorter intervals over all for oil changes and you've more than done your part. If it piles up, that's completely on GM and its there baby to cover the cost of a new engine. 

 

By the way the neighbor said he just had that coolant diverter contraption replaced on is truck, don't recall the miles that is on his truck now but certainly within the warranty period yet and so was all covered as he said there was a time when they were not covering that under the power train warranty but now they are as I believe he would be over the bumper to bumper warranty in distance I believe and certainly past in the three year time frame. 

 

My LZ0 was delivered new and it had an extra quart showing on the dipstick. That's when I went asking if it was factory, dealer/PDI, or some other error and the consensus was the factory adds an extra quart. I fill with the recommended 7 quarts, not 8, and just keep an eye on it. Nice to know there's apparently an extra quart of capacity in the sump, I guess.

 

I have not cut open the filters. I use AcDelco PF66's. I'm now in the "critical" period where most of the LZ0's tend to fail if they have a bad thrust bearing. Ugh. I don't want to know, I just want it to either explode, or be fine.

 

The coolant control valve is a real Duesy. My LZ0 reportedly has the newer design CCV. I'm getting a faint coolant smell after shutdown sometimes. I was hoping it was just burping and other seating of hoses but at 3k miles I'm still getting it. If the engine doesn't blow up, I'll probably take it in for the coolant smell. The levels in the overflow (both for engine, and turbo circuit) are still full, so it can't be losing much.

Edited 1 hour ago by Atlas