[jfoj]

Do not forget, 7 quarts of oil will expand quite a bit once up to operating temperature.

As long as YOU know where the cold level should be from checking there should be no issue checking the engine oil cold.

 

[WDE46]

Just buy some of the newer model cars that have no engine oil dipstick at all!

You have to rely on the oil level sensor 100%.

I really think that is going too far. I am already annoyed by the lack of a transmission dipstick on this car. Lack of an oil one would kill me.

 

[WDE46]

Do not forget, 7 quarts of oil will expand quite a bit once up to operating temperature.

As long as YOU know where the cold level should be from checking there should be no issue checking the engine oil cold.

Good point, but the manual suggests the dipstick is designed for hot oil with some quantity still in the OFH and coating the surfaces of the engine.

 

[SD 328I]

On a side note, a new dipstick is like $15 at the dealership, I had to buy one because mine became inaccurate.

What happens is that the plastic indicator is glued on, over time, it actually starts getting loose and can move around quite a bit.

 

[jdstrickland]

Good point, but the manual suggests the dipstick is designed for hot oil with some quantity still in the OFH and coating the surfaces of the engine.

He's suggesting that if you check the oil while it is cold, the level will be low and one might put in more oil that will be too much when it is hot.

I'm 60, and I worked in a gas station when I was 15, and my father was a Used Car dealership while I was growing up, and in my years of driving and owning cars, I have never seen oil go from low when cold to proper when warm, or from proper when cold to over filled when warm. My data set, small as it is, makes me want to call Bullshit and see who has the better cards.

 

[Kubica]

Incorrect. BMW specifies to check oil 5 minutes after shutting down a fully warm engine. Coolant is to be checked cold in the morning, not oil.

Lol. BMW specifies a lot of things.

PROPER READING OF A DIPSTICK
Before engine start, pull the stick and wipe it. Put the stick back in then pull it out and read it. If the oil is anywhere between the high mark and the low mark, the level is okay. If the level is at or below the low mark, add a full quart or liter, depending on your market and how they package the oil.

Yes.

Checking oil in a cold engine is the best check. If the engine has been running, then you want to wait 5 minutes for it to drain down to the oil pan.

Yes.

Verbatim from the 3 Series Bentley Bible, the Book of Maintenance, Chapter 020-11, Verses 1-4:

Engine oil level is checked with a dipstick (arrow ((pointing to picture of E46 dipstick)) ) in engine block.

-Check oil level with car on a level surface, after engine has been stopped for at least a few minutes.

-Check level by pulling out dipstick and wiping it clean. Reinsert it all way and withdraw it again.

-Oil level is correct if it is between two marks near end of stick.

Tomato, tomahto, potato, potahto... :hmm:

BMW Manual:

Read it and weep.

Bentley sucks. You're telling me that it's best to check the oil level while there's oil sloshing around everywhere and not while it's static? That's ridiculous.

In that scenario (5 minutes after shutdown) the "oil level" is a function of the oil's viscosity. Makes no sense to measure anything that way.

He's suggesting that if you check the oil while it is cold, the level will be low and one might put in more oil that will be too much when it is hot.

I'm 60, and I worked in a gas station when I was 15, and my father was a Used Car dealership while I was growing up, and in my years of driving and owning cars, I have never seen oil go from low when cold to proper when warm, or from proper when cold to over filled when warm. My data set, small as it is, makes me want to call Bullshit and see who has the better cards.

If I pull the dipstick five minutes after I get a low oil warning light at shutdown, the oil still reads halfway up the dipstick.

M54's run better with the oil slightly overfilled when checked on a dead cold engine.

 

[WDE46]

BMW specifies the level measurement how they designed it to be read. This isn't one of those "BMW is wrong" things. This is a "BMW knows what level it's supposed to read 5 minutes after shutting of a warm engine so here we marked it on this stick for you" kind of thing. This has nothing to do with the perfectly valid arguments against things like the 15,000 mile OCI.

Oil level is a function of its density, not viscosity.

 

[TopasE46]

I have never seen oil go from low when cold to proper when warm, or from proper when cold to over filled when warm.

Not calling your bluff, but I work at a Ford dealership on diesels that hold 15 quarts of 15w-40. I've personally seen oil level rise about 1/4 of an inch from stone cold to operating temp. Same with transmission Fluid.

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[jdstrickland]

BMW specifies the level measurement how they designed it to be read. This isn't one of those "BMW is wrong" things. This is a "BMW knows what level it's supposed to read 5 minutes after shutting of a warm engine so here we marked it on this stick for you" kind of thing. This has nothing to do with the perfectly valid arguments against things like the 15,000 mile OCI.

Oil level is a function of its density, not viscosity.

But,if the engine is checked for proper oil level the next morning, then it has met the 5 minutes requirement. It has actually exceeded the minimum wait time by several hours.

You state this requirement as if the car must be warmed up fully, then wait five minutes else the information will not be right. If the engine is never started, then it has been more than 5 minutes since it was shut down, and the entire purpose of waiting has been fulfilled.

Check the oil when the engine is stone-cold, or, wait 5 minutes after the engine has been running and has attained full operating temp. In any case, the car needs to be on level ground.

Whatever, the way the OP opened the discussion is nonsensical, and the only way to move forward is to drain all of the oil, refill with the full 7 quarts, then look to see where the level is on the dip stick. He got a low oil light and put in one half quart, and then posted that the oil was not on the dipstick. 1.) why only a half quart? 2.) why is he alarmed that he needed a quart, he says elsewhere that his car goes through oil at a quart per 1000 or 2000 miles, whatever.

He's concerned that the dipstick has an error, so what he needs to know is how to calibrate it. You do that from a known condition, 7 full quarts of oil, run the engine for a few minutes, then let it rest for several more minutes -- use the Run Time to inspect for leaks, mostly from the drain plug and the oil filter housing but no need to limit yourself. After 5 or more minutes of rest, pull the dip stick and wipe it clean and put it back in. Pull it a second time and hold it horizontal to the floor and observe the oil level relative to the notches cut into the plastic on the end of the stick. The oil should be at the top mark.

Until the next oil change is due, when checking the oil, allow sufficient time for it to drain to the oil pan -- there is no such thing as allowing too much time, so the next morning is good. Pull the stick and wipe it clean, put it in and pull it out again. Hold the stick horizontal to the floor and observe the level. ANYWHERE BETWEEN THE UPPER AND LOWER MARK IS OKAY. If at or below the lower mark, then add oil by the full measure, quart or liter, to get the level between the two marks.

 

[jfoj]

He's suggesting that if you check the oil while it is cold, the level will be low and one might put in more oil that will be too much when it is hot.

I'm 60, and I worked in a gas station when I was 15, and my father was a Used Car dealership while I was growing up, and in my years of driving and owning cars, I have never seen oil go from low when cold to proper when warm, or from proper when cold to over filled when warm. My data set, small as it is, makes me want to call Bullshit and see who has the better cards.

http://www.engineeringtoolbox.com/cubical-expansion-coefficients-d_1262.html

Last time I checked almost all matter expands when warmed up. Basic physics and thermal properties.

Engine oil runs at about 10-20F warmer than engine coolant under most situations as I recall. Also keep in mind it takes 2-4 times longer for the engine oil to come up to operating temperature than the engine coolant.

If the oil does not expand, why do the car manufactures suggest you check the engine oil warm in the first place? This is also why there is likely a fill range on the dipstick.

Same goes for automatic transmissions, always check warm or hot depending on the checking method, and also look at any power steering reservoir, there are cold and warm fill marks.

One reason many car manufactures choose warm level check is you can control the warm temperature far easier than the "cold" temperature. Cold could be 80F or it could be -20F.

My point is anyone can determine the baseline cold levels on their own car as long as they properly check and fill when warm, then let the engine/car cool off they check at a consistent temperature and determine where the baseline for the cold oil level. This will be just a accurate as warm checking.

As they say, it is all relative.

 

[jfoj]

WDE46, time for oil expansion science!

 

[jdstrickland]

http://www.engineeringtoolbox.com/cubical-expansion-coefficients-d_1262.html

Last time I checked almost all matter expands when warmed up. Basic physics and thermal properties.

Engine oil runs at about 10-20F warmer than engine coolant under most situations as I recall. Also keep in mind it takes 2-4 times longer for the engine oil to come up to operating temperature than the engine coolant.

If the oil does not expand, why do the car manufactures suggest you check the engine oil warm in the first place? This is also why there is likely a fill range on the dipstick.

Same goes for automatic transmissions, always check warm or hot depending on the checking method, and also look at any power steering reservoir, there are cold and warm fill marks.

One reason many car manufactures choose warm level check is you can control the warm temperature far easier than the "cold" temperature. Cold could be 80F or it could be -20F.

My point is anyone can determine the baseline cold levels on their own car as long as they properly check and fill when warm, then let the engine/car cool off they check at a consistent temperature and determine where the baseline for the cold oil level. This will be just a accurate as warm checking.

As they say, it is all relative.

That's why I say that if the oil is anywhere on the stick between the marks, then it is okay, because when it is hot and there is more, then it is full. If it is below the minimum mark, then a quart will put the new level between the two marks, and it is okay.

Wow!

The instance of an automatic transmission is a little bit different than the engine. You want as much fluid as you can get, so you want it to be warm, engine running, and in Park or Neutral -- it actually tells you on the dipstick in many cases what, exactly, to do. And transmission fluid is to oil as lake water is to sea water, it's wet but entirely different.

In a Ford, the difference in the low and the full line was once only a pint, so the margins are much tighter than the oil in the engine.

You are putting a fine point on a topic that can be written about with a Magic Marker.

If the oil level is anywhere between the marks when cold, it is fine. If it not at the high mark when it is hot, it will be pretty close to the low mark when it is cold, but it doesn't matter because it's still within the statement that if it's between the marks then it's okay. If it is below the mark when cold, it is also below the high mark when it is hot. There is a very narrow window, maybe, where the oil can be low when cold, and adding a quart will go above the upper mark when hot, but there is no issue with a couple of extra ounces, and if you care then wait a tank of gas while a little more oil seeps out or blows off, then put in a quart.

 

[WDE46]

WDE46, time for oil expansion science!

lol. I'm sure the height change is insignificant given the wide surface area of the fluid in the oil pan.

WolframAlpha doesn't have density information.

 

[xi-xi]

BMW Manual:

Read it and weep.

Get serious. I'm sorry, but this interpretation is nutty. That's not an instruction to wait exactly 5 minutes then check the oil level; it's an instruction to wait AT LEAST 5 minutes before checking the oil level, i.e., wait 5 minutes or 24 hours or 24 days, whatever, but wait at least 5 minutes, then check the oil level.

This is pretty common sense stuff and you're reading waaaay too much into that blurb
---------------

Upon further reflection, I will say this; they are instructing that the oil should be checked while warm, I get that. 5 minutes or 30 or even an hour isn't going to mean squat. I really doubt that oil expansion is going make a huge difference in the level. During the summer I wouldn't even bother warming it up.

 

[WDE46]

It's fine to check it cold and all that, I'm just posting what BMW says to do. It doesn't say wait at least 5 minutes either. It says wait approximately 5 minutes. That'll let most of the oil in the passages clear out.

I don have a problem with this because I check it after work anyway.


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[cityjohn]

Dipstick not reading correctly?

 

[screamotaku]

Ive got a great idea. Let's start an entire thread on how to check oil! ... said no one ever.

 

[Silver325]

So I threw the rest of the oil in my car and now it's displaying on the dipstick. So I suppose I was just VERY low. Darn. My question now is, where the eff is the oil going? I know I burn a small amount of oil which I know isn't uncommon for M54's but this is just strange. Any ideas? Once again I have no signs of leaks anywhere not even in the coolant.... everything is running fine. My car idles VERY well, I've never had a misfire, I just cannot think what is causing this much oil to just vanish... what am I not considering?

OP, seems your post got pulled way off track. When my car started loosing a lot of oil, I discovered it was the oil filter housing gasket that went bad. The oil will weep down along the side of the motor. It is hard to see unless you look in the right spot.

Take a look at this DIY post to see where to look. It's a pretty easy repair. I went from loosing a quart every two weeks, to now almost nothing.

http://forum.e46fanatics.com/showthread.php?t=657887&highlight=oil+filter+housing+gasket

Hope this helps!

 

[screamotaku]

Thank's Silver325 but I just replaced the OFHG maybe 3 months ago. I figured out what my issue was, it has been burning it at a normal rate I just haven't been checking as often as I normally do and I just let it get way too low. Thank's though!

 

[JohnnyFaire]

Do not forget, 7 quarts of oil will expand quite a bit once up to operating temperature.

As long as YOU know where the cold level should be from checking there should be no issue checking the engine oil cold.

Good point, but the manual suggests the dipstick is designed for hot oil with some quantity still in the OFH and coating the surfaces of the engine.

***x1f603;