Oil Consumption

asilverblazer · June 5

2 minutes ago, KARNUT said:

Operating temperature when drained. (Hot)

Oil is cool going in. (Cool)

The amount that’s called for goes in. (X volume, cool)

Then it’s started. (Warmed)

Then shut off (Drain back time?)

If needed filled to the top of the line. (X + Y)

The oil is at the top hatch in all my vehicles. (Hot)

That's a bunch more variables, Grumpy might be able to calculate it, I'm not going to.

Thanks for sharing, number 6 seems risky given the owner's manual statements:

Quote

Follow these guidelines: To get an accurate reading, park the vehicle on level ground. Check the engine oil level after the engine has been off for at least two hours. Checking the engine oil level on steep grades or too soon after engine shutoff can result in incorrect readings. Accuracy improves when checking a cold engine prior to starting. Remove the dipstick and check the level. If unable to wait two hours, the engine must be off for at least 15 minutes if the engine is warm, or at least 30 minutes if the engine is not warm. Pull out the dipstick, wipe it with a clean paper towel or cloth, then push it back in all the way. Remove it again, keeping the tip down, and check the level.

asilverblazer · June 5

8 minutes ago, riddler said:

Expansion and recontraction not consumption

It could be consumption too, GM allows (acknowledges, expects?) some loss.

riddler · June 5

7 minutes ago, asilverblazer said:

It could be consumption too, GM allows (acknowledges, expects?) some loss.

Only when its convenient for GM. Its called ass covering. the 6.6 that consumes.

Chuck FB · June 5

1 hour ago, asilverblazer said:

Again, every vehicle I've touched I drain out less than what I put in. (Further evidence is I use the new containers to take in the old oil, they never overflow, and there's plenty room to pour more in when the drain pan is empty. Usually, an empty quart bottle on the two newest trucks with room to spare in another.)

Pull drain plug and let drain into catch pan. Pull filter and dump into catch pan, set upside down on the fancy little filter holder to drain 'more'. Take a few minutes to clean up, get new stuff out, etc. Clean drain plug, clean oil filter sealing surface, inspect things, whatever... Put drain plug in and install new filter. Fill engine with new oil set aside the new (empty) containers. Pour the old oil in the new containers, note the markings on the side, put old filter in the new filter box. Wipe out pan. Throw away one empty quart container. Cap the others, one will usually have some room in it still.

There may be "some drop" on the dip stick, it's never been a quantity to warrant measuring for sake of comparing to any previous reading. Of course, given this conversation I'll be making much more careful observations of the reading on the dipstick, to see what 1 quart plus minus looks like within the marked area.

However, the dipstick, in my opinion, isn't the most accurate gauge to determine "oil consumption, use, etc." not that I have any better alternative. I think it's best suited to determine if engine has a reasonable amount of oil to prevent failure.

If an EXACT amount was required, it wouldn't have a range specified, it would have a single mark. GM knows some oil will be lost, note the acceptable consumption per mile. The larger capacity pans that have come about in the last decade I think are a result of that, to allow for some between changes without the result of oil starvation.

There are probably a few factors involved with the higher oil capacity of newer engines that have a similar engine displacement relative to older engines as well as the smaller turbo pickup engines with a higher capacity for their engine cubic inch size. More oil giving a longer engine run time before the oil is contaminated and sheared down etc. More cooling available with more volume. More oil consumption cushion before bad things happen.

The horsepower newer engines put out would certainly play into the higher volume of oil that helps control the temperatures as after all engines of a similar size putting out twice the horse power means more fuel used and more heat created requiring a better coolant package with coolant and oil with oil cooler etc. To show the engineered difference for example in oil volume for the very same engine series/block/cubic inch displacement on a JD four wheel drive tractor I have that is rated at 425 hp it has an oil capacity/pan sized for 44 quarts, the largest series of tractor of that time was rated for 530 hp and had a pan capacity of 63.5 quarts.

Grumpy Bear · June 6

4 hours ago, riddler said:

Oil dipsticks have a range (usually marked with "L" and "F" or a crosshatched area) because oil naturally expands as it gets hot. This range gives your engine a safe margin of operation, ensuring there is enough oil to properly lubricate moving parts without overfilling it past the maximum

Yea, not the reason. There is a nominal 1 quart/liter range on that stick. (Autos/light trucks) Some small metrics are a 1/2 liter. Gives a fella an idea how much to add. Your book should say something like, "Add when the level falls to the lower mark". Does in every one I've owned.

Grumpy Bear · June 6

2 hours ago, Chuck FB said:

There are probably a few factors involved with the higher oil capacity of newer engines

Biggest reason is fuel dilution rates of GDI engines.

riddler · June 6

4 minutes ago, Grumpy Bear said:

Yea, not the reason. There is a nominal 1 quart/liter range on that stick. (Autos/light trucks) Some small metrics are a 1/2 liter. Gives a fella an idea how much to add. Your book should say something like, "Add when the level falls to the lower mark". Does in every one I've owned.

The point is the purpose for the range on the dipstick is for expansion of the oil as it gets hot.

Homer1959 · June 6

1 hour ago, riddler said:

The point is the purpose for the range on the dipstick is for expansion of the oil as it gets hot.

From the owner manual Sierra hd 2025 6.6 gas how to check engine oil level :

To get an accurate reading, park the vehicle

on level ground.

Check the engine oil level

after the engine has been off for at least

two hours.

Checking the engine oil level

on steep grades or too soon after engine

shutoff can result in incorrect readings.

Accuracy improves when checking a cold

engine prior to starting. Remove the

dipstick and check the level.

So, according to you, Riddler, with the engine cold we should aim for the low mark on the dipstick, and the high mark when the engine is at operating temperature? So you’re saying the engine oil expands by a quart... humm... I guess that's something GM dont know

riddler · June 6

20 minutes ago, Homer1959 said:

From the owner manual Sierra hd 2025 6.6 gas how to check engine oil level :

To get an accurate reading, park the vehicle

on level ground.

Check the engine oil level

after the engine has been off for at least

two hours.

Checking the engine oil level

on steep grades or too soon after engine

shutoff can result in incorrect readings.

Accuracy improves when checking a cold

engine prior to starting. Remove the

dipstick and check the level.

So, according to you, Riddler, with the engine cold we should aim for the low mark on the dipstick, and the high mark when the engine is at operating temperature? So you’re saying the engine oil expands by a quart... humm... I guess that's something GM dont know

Humm! Homer, if you read what I actually wrote, you might gain understanding. SMH.....

Grumpy Bear · June 6

2 hours ago, riddler said:

The point is the purpose for the range on the dipstick is for expansion of the oil as it gets hot.

Then you're saying the motor is full cold on the lowest mark of the sticks range. So,... you intentionally short your oil change a full quart? Yikes!!

Every motor I've ever changed oil in over 64 years of oil changing that level has been at the top when the book amount of oil is put in and level checked by the OEM procedure. Kind'a the point of the top of the range. A double check if you will.

Have any idea how much of a motors oil is not in the pan at peak pump volume? (second stage at red line). Depends on the motor but 2 quarts isn't out of the question. This one quart range got started when pans held 3-1/2 - 4 quarts. With 1.5 - 2 quarts circulating a motor 1 quart low would, could and often did spin a bearing as the pump suction became uncovered. Air is a pour lubricant. That low mark told the dummy operating it he was a tea spoon away for pulling the pin on that grenade.

We have a bit more cushion today with much larger pans, windage trays and such, but we also have more oil in circulation and rings that are not as adept at oil control and some truly strange pan venting systems that will suck a pan dry enough to be trouble pretty quick if not in good repair.

Give an automatic transmission stick a good look (If you can find a trans with a stick). They are clearly marked for both a cold range and a hot range and many like the JATCO's even have a table in the book showing level V temperature by degrees and voltage and mm on the stick. Even my 6L80E is setup that way.

Engine Oil pan sticks are legacy one quart markers to keep Joey Bumpstick's motor in play.

riddler · June 6

8 minutes ago, Grumpy Bear said:

Then you're saying the motor is full cold on the lowest mark of the sticks range. So,... you intentionally short your oil change a full quart? Yikes!!

Every motor I've ever changed oil in over 64 years of oil changing that level has been at the top when the book amount of oil is put in and level checked by the OEM procedure. Kind'a the point of the top of the range. A double check if you will.

Have any idea how much of a motors oil is not in the pan at peak pump volume? (second stage at red line). Depends on the motor but 2 quarts isn't out of the question. This one quart range got started when pans held 3-1/2 - 4 quarts. With 1.5 - 2 quarts circulating a motor 1 quart low would, could and often did spin a bearing as the pump suction became uncovered. Air is a pour lubricant. That low mark told the dummy operating it he was a tea spoon away for pulling the pin on that grenade.

We have a bit more cushion today with much larger pans, windage trays and such, but we also have more oil in circulation and rings that are not as adept at oil control and some truly strange pan venting systems that will suck a pan dry enough to be trouble pretty quick if not in good repair.

Give an automatic transmission stick a good look (If you can find a trans with a stick). They are clearly marked for both a cold range and a hot range and many like the JATCO's even have a table in the book showing level V temperature by degrees and voltage and mm on the stick. Even my 6L80E is setup that way.

Engine Oil pan sticks are legacy one quart markers to keep Joey Bumpstick's motor in play.

Over engineering everything LOL

KARNUT · June 6

7 hours ago, Grumpy Bear said:

Then you're saying the motor is full cold on the lowest mark of the sticks range. So,... you intentionally short your oil change a full quart? Yikes!!

Every motor I've ever changed oil in over 64 years of oil changing that level has been at the top when the book amount of oil is put in and level checked by the OEM procedure. Kind'a the point of the top of the range. A double check if you will.

Have any idea how much of a motors oil is not in the pan at peak pump volume? (second stage at red line). Depends on the motor but 2 quarts isn't out of the question. This one quart range got started when pans held 3-1/2 - 4 quarts. With 1.5 - 2 quarts circulating a motor 1 quart low would, could and often did spin a bearing as the pump suction became uncovered. Air is a pour lubricant. That low mark told the dummy operating it he was a tea spoon away for pulling the pin on that grenade.

We have a bit more cushion today with much larger pans, windage trays and such, but we also have more oil in circulation and rings that are not as adept at oil control and some truly strange pan venting systems that will suck a pan dry enough to be trouble pretty quick if not in good repair.

Give an automatic transmission stick a good look (If you can find a trans with a stick). They are clearly marked for both a cold range and a hot range and many like the JATCO's even have a table in the book showing level V temperature by degrees and voltage and mm on the stick. Even my 6L80E is setup that way.

Engine Oil pan sticks are legacy one quart markers to keep Joey Bumpstick's motor in play.

As you know transmission fluid is or acts like hydraulic fluid. I don’t think it expands much hot. Never really gave it much thought. I imagine you could check it without your vehicle running or warmed up as long as you knew it was full before hand. I was conditioned to do it one way, so that was that. Oil checking was always after cool down for drain back. But usually is done in my case because I live on a hill while getting gas. Even at home once knowing the oil is full you can check on a hill. Doing it in the same spot with the dipstick marked. All things considered there’s wiggle room that’s why there’s an add and full line. We won’t want to start out at the lowest line. Something Ive rarely experienced. Even back when I went extended driving 50K miles a year or more. That’s the interesting part of this thread when a normal phenomenon. Like checking fluids can turn into such a debate.

Edited June 6 by KARNUT

riddler · June 6

9 hours ago, Grumpy Bear said:

Then you're saying the motor is full cold on the lowest mark of the sticks range. So,... you intentionally short your oil change a full quart? Yikes!!

Every motor I've ever changed oil in over 64 years of oil changing that level has been at the top when the book amount of oil is put in and level checked by the OEM procedure. Kind'a the point of the top of the range. A double check if you will.

Have any idea how much of a motors oil is not in the pan at peak pump volume? (second stage at red line). Depends on the motor but 2 quarts isn't out of the question. This one quart range got started when pans held 3-1/2 - 4 quarts. With 1.5 - 2 quarts circulating a motor 1 quart low would, could and often did spin a bearing as the pump suction became uncovered. Air is a pour lubricant. That low mark told the dummy operating it he was a tea spoon away for pulling the pin on that grenade.

We have a bit more cushion today with much larger pans, windage trays and such, but we also have more oil in circulation and rings that are not as adept at oil control and some truly strange pan venting systems that will suck a pan dry enough to be trouble pretty quick if not in good repair.

Give an automatic transmission stick a good look (If you can find a trans with a stick). They are clearly marked for both a cold range and a hot range and many like the JATCO's even have a table in the book showing level V temperature by degrees and voltage and mm on the stick. Even my 6L80E is setup that way.

Engine Oil pan sticks are legacy one quart markers to keep Joey Bumpstick's motor in play.

For clarity: per the manufacturer the 6.6L takes 8 quarts of oil with a filter replacement. I always add that amount which puts near the top of the dipstick range.

diyer2 · June 6

It's amazing the different ways people think. Fluid expansion has never come into play in 50+ years. If the dipstick level, oil or trans is with in the marks is all that matters to me. I have always done oil checks on a cold engine.

Not saying that's right, just my way.

riddler · June 6

38 minutes ago, diyer2 said:

It's amazing the different ways people think. Fluid expansion has never come into play in 50+ years. If the dipstick level, oil or trans is with in the marks is all that matters to me. I have always done oil checks on a cold engine.

Not saying that's right, just my way.

Agree! According to all engine manufactures any area of the range is good. I check mine cold as well. But I have checked hot as well.