[XC3LLR8]

Took my wife's Mazda in for an oil change and they vacuumed out the oil from the dipstick, which I'd never seen before. All other times it was a typical gravity drain. Don't guess it would work for our cars since we don't have a dipstick shaft. They vacuumed out about 5.3 qts when the capacity is only 4.5. I asked why it was over capacity and they asked who filled it last and I replied "you did". LOL

The level on the dipstick always showed right at the full mark, so I never had any indication it was over capacity. Obviously not all was drained and they simply add the required 4.5 qts back in. Now it makes me wonder about the M240i and whether the electronic measurement would show us if it was over capacity, or does the green bar max out at the full mark? With the ZTK package having an additional oil cooler it also makes me wonder how much oil is not being drained.

Just an observation and something to keep in mind if you do your own oil changes on the M240i, like I do. Ours calls for 6.9 qts, and I've always added 6.75 qts just to make sure I don't overfill. Now I may change my routine to 6.5 qts and see what that registers on the electronic measurement.

[M2siast]

If the manual calls for 6.9 quarts, that’s how much you should put in during oil changes.
Obviously you’re fine putting half a quart less if wanted, but that means the oil will last shorter, and you run a higher risk of oil starvation during turns on a track, for example.

There’s no reason to put in less than indicated.

[XC3LLR8]

Originally Posted by M2siast

If the manual calls for 6.9 quarts, that’s how much you should put in during oil changes.
Obviously you’re fine putting half a quart less if wanted, but that means the oil will last shorter, and you run a higher risk of oil starvation during turns on a track, for example.

There’s no reason to put in less than indicated.

6.9 qts is the correct amount for an empty engine, which it was for its factory fill. And on the track I'd much rather have 6.4 qts than 7.4 qts.

My point is it appears there's a considerable amount of oil left in the engine/coolers/lines during a gravity drain on some cars, and now I'm curious how much is left in our cars. Also, curious if our electronic measurement will show us anything ABOVE the full line?

[Pentland]

I thought everyone had moved on from vacuuming out oil. I believe it tends to spray oil all over the engine internals on the way out, also spraying all the crap which would ordinarily gravitate to the bottomed and be drained away.

[XC3LLR8]

Originally Posted by Pentland

I thought everyone had moved on from vacuuming out oil. I believe it tends to spray oil all over the engine internals on the way out, also spraying all the crap which would ordinarily gravitate to the bottomed and be drained away.

Until I witnessed this about a week ago I had no idea vacuuming out oil was a thing.

Not sure how it would spray oil all over the engine as a long tube is inserted down the dipstick shaft to the bottom of the oil pan, which then sucks it out. Not clear on where/how the spraying would occur?

[danallxt]

Originally Posted by M2siast

If the manual calls for 6.9 quarts, that’s how much you should put in during oil changes.
Obviously you’re fine putting half a quart less if wanted, but that means the oil will last shorter, and you run a higher risk of oil starvation during turns on a track, for example.

There’s no reason to put in less than indicated.

There are very good reasons NOT to add what is indicated as capacity, that is to avoid overfilling. There is always some residue left, and it can vary. I've always changed my own oil on all my vehicles and never have been able to add the indicated "capacity" when bringing it up to full.

What is interesting is my manual does not state the oil capacity. In three locations it warns against too much oil. Even in the "tech data" section (which is woefully inadequate) the oil capacity is omitted. Perhaps i missed it...but i can find no reference to oil capacity in the owners manual (2022 US). I think they expect all BMW owners to have dealerships change oil as that complex operation is too technically involved for us.

[XC3LLR8]

Originally Posted by danallxt

There are very good reasons NOT to add what is indicated as capacity, that is to avoid overfilling. There is always some residue left, and it can vary. I've always changed my own oil on all my vehicles and never have been able to add the indicated "capacity" when bringing it up to full.

What is interesting is my manual does not state the oil capacity. In three locations it warns against too much oil. Even in the "tech data" section (which is woefully inadequate) the oil capacity is omitted. Perhaps i missed it...but i can find no reference to oil capacity in the owners manual (2022 US). I think they expect all BMW owners to have dealerships change oil as that complex operation is too technically involved for us.

I've tried several different key word searches in the owner's manual and I can not locate any oil capacity information - probably the only owner's manual I've ever had w/o this info.

What's funny is this car probably has the easiest oil change of any car I've owned.

[M2siast]

Originally Posted by XC3LLR8

6.9 qts is the correct amount for an empty engine, which it was for its factory fill. And on the track I'd much rather have 6.4 qts than 7.4 qts.

Source for this information that the quantity we’re informed is what was factory filled, and not the capacity during change? First time I hear anyone say that.

You are way overthinking this.

And the 7.4 quarts example is a strawman argument, since no one is talking about it.

Originally Posted by danallxt

There are very good reasons NOT to add what is indicated as capacity, that is to avoid overfilling. There is always some residue left, and it can vary. I've always changed my own oil on all my vehicles and never have been able to add the indicated "capacity" when bringing it up to full.

So you’re saying following the manual ends in overfilling, that’s a first as well as hearing that you could never fill it up with capacity before.

I’ve been doing my own oil changes in BMWs without dipsticks for several years and hundreds of thousands of kilometres and never once overthought about this… 7 quarts/6.5 litres and you’re good to go.

I guess the old adage that oil discussions are never ending rings true here. There’s always something new coming up… I’ll see myself out

[Pentland]

Originally Posted by XC3LLR8

I've tried several different key word searches in the owner's manual and I can not locate any oil capacity information - probably the only owner's manual I've ever had w/o this info.

What's funny is this car probably has the easiest oil change of any car I've owned.

That’s because it’s not a service manual. It’s an owner’s handbook.
Would you expect it to have the spark plug gaps in there too

[aiursblade]

Originally Posted by XC3LLR8

Until I witnessed this about a week ago I had no idea vacuuming out oil was a thing.

Not sure how it would spray oil all over the engine as a long tube is inserted down the dipstick shaft to the bottom of the oil pan, which then sucks it out. Not clear on where/how the spraying would occur?

Yea vacuum oil changes are the bees knees. Did all of the changes on my GTI that way and it turned a messy hour long process (if you had to wait for oil to cool down), into a 15-20 min job that you could do even if you had just driven the car.
No detrimental effects whatsoever, and it got all the oil out same as a normal drain. Was even mentioned in the VW service guidelines.

[M2siast]

Originally Posted by Pentland

That’s because it’s not a service manual. It’s an owner’s handbook.
Would you expect it to have the spark plug gaps in there too

That used to be in the manual too.
These omissions reflect the times we live in…
Plus, BMW charges money for service manual access and shut down whoever was sharing the information. We can’t even torque the wheels after a wheel change over without information.

[XC3LLR8]

Originally Posted by M2siast

Source for this information that the quantity we’re informed is what was factory filled, and not the capacity during change? First time I hear anyone say that.

You are way overthinking this.

And the 7.4 quarts example is a strawman argument, since no one is talking about it.

The fact you've never heard anything different is a good sign the factory fill volume is the same as the oil change volume. Feel free to research this and let us know if it's different.

The 7.4 quarts vs. 6.4 quarts came from the .5 quarts difference between what was vacuumed out and what the recommended volume is in my wife's car. I used that .5 quarts as the example for our car's volume of 6.9 quarts of being .5 quarts above vs. below the recommended volume. Apologies the simple math came across as a "strawman argument".

[XC3LLR8]

Originally Posted by Pentland

That’s because it’s not a service manual. It’s an owner’s handbook.
Would you expect it to have the spark plug gaps in there too

Yes, yes I would. From my 2020 Camaro SS 1LE owner's manual...

[winter.zed]

Originally Posted by XC3LLR8

Took my wife's Mazda in for an oil change and they vacuumed out the oil from the dipstick, which I'd never seen before.

Vacuuming oil out used to be "the standard way" of changing oil back 20-ish years ago in the TDI community, at least.
I had 3 VW/Audi diesels over the years and the Pela 6000 was everybody's favourite extractor.

FWIW - I could always get more oil out with the Pela extractor compared to regular gravitational drain. By how much - depended on the shape of the oil pan, location of drain hole, etc.

[M2siast]

Originally Posted by XC3LLR8

The fact you've never heard anything different is a good sign the factory fill volume is the same as the oil change volume. Feel free to research this and let us know if it's different.

The 7.4 quarts vs. 6.4 quarts came from the .5 quarts difference between what was vacuumed out and what the recommended volume is in my wife's car. I used that .5 quarts as the example for our car's volume of 6.9 quarts of being .5 quarts above vs. below the recommended volume. Apologies the simple math came across as a "strawman argument".

Got it, thanks! Just to clarify, I mentioned overfilling wasn’t a part of the discussion because the capacity would indicate “filling capacity” (so, “full” or “max”).
Every engine has a MIN/MAX range, and that range is 1 quart in BMW engines. So, running 0.5 below MAX is totally fine.
0.5 above MAX, not so much…

I’d rather do 7 quarts than 6.5. But not 7.5 over 7 (or even 6.5)

[XC3LLR8]

Originally Posted by winter.zed

Vacuuming oil out used to be "the standard way" of changing oil back 20-ish years ago in the TDI community, at least.
I had 3 VW/Audi diesels over the years and the Pela 6000 was everybody's favourite extractor.

FWIW - I could always get more oil out with the Pela extractor compared to regular gravitational drain. By how much - depended on the shape of the oil pan, location of drain hole, etc.

Interesting - thanks for the info.

I'd be tempted to use the vacuum method with this car if we had that option. And with the oil filter's access under the hood, no need to ever get under the car.

[XC3LLR8]

Originally Posted by M2siast

Got it, thanks! Just to clarify, I mentioned overfilling wasn’t a part of the discussion because the capacity would indicate “filling capacity” (so, “full” or “max”).
Every engine has a MIN/MAX range, and that range is 1 quart in BMW engines. So, running 0.5 below MAX is totally fine.
0.5 above MAX, not so much…

I’d rather do 7 quarts than 6.5. But not 7.5 over 7 (or even 6.5)

Somewhere there was another thread where some of this was touched on. My last oil change I did 6.75 qts and the car registered full (max). Someone else went a little lower and add 6.5 qts for their oil change, and again the car registered full (max).

This is what makes me suspicious of a lot more oil being left in the engine during an oil change, and then adding 6.9 qts could be taking us well over 6.9 qts actually in the engine. Does the electronic dip stick show us anything over full (max)???

[XC3LLR8]

M2siast I just saw you have a new M2. Does it also call for 6.9 qts, or does the extra turbo require a little more capacity?

[M2siast]

Originally Posted by XC3LLR8

M2siast I just saw you have a new M2. Does it also call for 6.9 qts, or does the extra turbo require a little more capacity?

Same thing AFAIK.

And, like you, I have trouble finding the information and am frustrated the manual doesn’t say it outright. It used to!

[M2siast]

Originally Posted by XC3LLR8

Somewhere there was another thread where some of this was touched on. My last oil change I did 6.75 qts and the car registered full (max). Someone else went a little lower and add 6.5 qts for their oil change, and again the car registered full (max).

This is what makes me suspicious of a lot more oil being left in the engine during an oil change, and then adding 6.9 qts could be taking us well over 6.9 qts actually in the engine. Does the electronic dip stick show us anything over full (max)???

One thing to note is that the “virtual dipstick” will never be accurate 100%. It operates in a range because of how it functions.

You said it registered full with 6.75, which I trust. It would show full from 6.5 to 7, based on my experience. Even less than 6.5 would register as full I believe.

It doesn’t mean it would show as “overfilled” if you had done 7. Hence my “you’re overthinking it”. No need to overthink it. 7 quarts and call it a day.

So, the way the car measures the level is by observing HOW LONG the oil goes from one temperature to another when it heats up.
Many factors at play for that sensor to read something different based on how long the oil took to go from 40 to 180 degrees for example. That’s why there’s a big margin for error. The capacity is what we should put in the engine, and it takes quite a bit more to overfill.

[M2siast]

BTW, the N52 takes 6.5 litres as well. No turbo. No oil cooler in some models.

So does the N54 (2 turbos). And the N55.
And the B58.
And the S58.

See where I’m going?

[XC3LLR8]

Originally Posted by M2siast

One thing to note is that the “virtual dipstick” will never be accurate 100%. It operates in a range because of how it functions.

You said it registered full with 6.75, which I trust. It would show full from 6.5 to 7, based on my experience. Even less than 6.5 would register as full I believe.

It doesn’t mean it would show as “overfilled” if you had done 7. Hence my “you’re overthinking it”. No need to overthink it. 7 quarts and call it a day.

So, the way the car measures the level is by observing HOW LONG the oil goes from one temperature to another when it heats up.
Many factors at play for that sensor to read something different based on how long the oil took to go from 40 to 180 degrees for example. That’s why there’s a big margin for error. The capacity is what we should put in the engine, and it takes quite a bit more to overfill.

I was under the impression the BMW design of the OZS system was extremely accurate, and the dielectric energy in the oil is read by a capacitor, which then reflects the level of the top quart as our electronic dipstick. The engine needs to be at a certain temperature to accomplish this, but I didn't think it's reading a temperature variance to determine the level.