Dipstick - Ever Notice This?

it's amazing how worked up some people get here about maybe a 1/8" difference on the dipstick marker.
try this: check your oil in the morning after it's been sitting overnight (take a picture of it); now get the engine nice and hot, let it sit for 20 min (the oil will still be really hot), note the dipstick and take another picture of it. I promise that that the difference between the two be negligible
Done that a while ago and I re-posted comparison pictures in post #9 in this thread.

And the oil levels are almost the same from a hot engine and a cold engine with the reason I stated previously.
 
I think it's pretty obvious what they mean when they tell you to warm up the engine in the previous step. But if that's the way you want to interpret it, that's fine. It's your car, do what you want.
The problem to me is you claimed Mazda specifies checking the oil level not when the engine is cold, and this isn't a matter of opinion, its a statement of fact.

But in fact Mazda has never mentioned warm or cold, only says wait for at least 5 minutes.
 
I think it's pretty obvious what they mean when they tell you to warm up the engine in the previous step. But if that's the way you want to interpret it, that's fine. It's your car, do what you want.
It's obvious to me that they mean exactly what they say. Wait at least 5 minutes. That means anywhere from 5 minutes to infinity.

You Canadians... :D
 
Again, do what you want. If you want to focus on that one single step and disregard the previous direction to warm the car up, go ahead. Why bother including a step to warm up the engine if they didn't want you to check the oil level when warm? <- (This is a rhetorical question, btw)
 
What does me being Canadian have to do with anything being discussed??
Again, do what you want. If you want to focus on that one single step and disregard the previous direction to warm the car up, go ahead. Why bother including a step to warm up the engine if they didn't want you to check the oil level when warm? <- (This is a rhetorical question, btw)
It was a light hearted joke that I guess you don't get.

The whole idea of warming the engine up, has to do with oil changes, not periodic checks. At the end of the day, neither of us are wrong.
 
This topic does bring up more traffic for the forum on Friday ⋯ ;):whistle:

Like I’ve said many times before, check oil level hot or cold as you prefer, it won’t make too much difference and it’s been proven by comparison pictures.

To me, I like to check the oil level the first thing in the morning. It’s easier to do with only one pull, and it’s a lot easier to see the oil level on the dipstick.
 
They might mention the warm up and 5 minute interval in case the oil has just been changed. It doesn't seem necessary just to monitor the oil level.
 
The whole idea of warming the engine up, has to do with oil changes, not periodic checks.

It applies to any instance of inspecting the oil level. It isn't specific to oil changes.

1.JPG
 
It applies to any instance of inspecting the oil level. It isn't specific to oil changes.

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Using your words... I think it's pretty obvious that they mean after an oil change. :)

I've been changing and checking oil levels for longer than most people on this forum have been alive. There have been numerous tests regarding when the level is checked. I have not seen anyone claim a discernible difference between cold and after waiting 5 minutes after shut-off. This is why I said neither way is wrong. I'm not sure why some people get so worked up about this.
 
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Using your words... I think it's pretty obvious that they mean after an oil change. :)

I've been changing and checking oil levels for longer than most people on this forum have been alive. There have been numerous tests regarding when the level is checked. I have not seen anyone claim a disenable difference between cold and after waiting 5 minutes after shut-off. This is why I said neither way is wrong. I'm not sure why some people get so worked up about this.

I think we can all agree that this is just going in circles now.
 
It boils down to individual preference. This debate has been revisited a few times here already. Some people can't read the dipstick on a warm engine, so they check it cold. Others can read the oil level when warm with no issue.

The only thing to note is that, as you mentioned, Mazda specifies when to check the oil level, and it isn't when the engine is cold. Saying that the cold check is "more accurate" is false. It's easier for those who can't read the dipstick on a warm engine, but it's less accurate according to the authority (Mazda). This isn't a matter of opinion, its a statement of fact.
The problem is people have a harder time figuring out the reading after the engine has been running. When cold all the oil is out of the dip stick tube. It is easier to get a good reading.
As far as Mazda stating to get the car to normal operating temperature before checking the oil is, it saves a step. If the engine locks up you don't have to bother checking the oil. It was too low. :ROFLMAO:
 
Again, do what you want. If you want to focus on that one single step and disregard the previous direction to warm the car up, go ahead. Why bother including a step to warm up the engine if they didn't want you to check the oil level when warm? <- (This is a rhetorical question, btw)

I'm going to have to agree with sm1ke here. Why would Mazda say to warm the car up at all if they didn't want the oil checked while the engine, and oil, were warmed up?

Yes, they didn't explicitly say that the oil should be warm but if they didn't want it to be warm why would they say to start the car and wait at least 5 mins after shutoff to check the oil? To me that says check while warm.

6 of one half a dozen of the other. Check it both warm and cold and average the readings.

This is why the dipstick has a range to indicate the amount of oil, not a specific mark to indicate the level.

YMMV
 
I'm going to have to agree with sm1ke here. Why would Mazda say to warm the car up at all if they didn't want the oil checked while the engine, and oil, were warmed up?

Yes, they didn't explicitly say that the oil should be warm but if they didn't want it to be warm why would they say to start the car and wait at least 5 mins after shutoff to check the oil? To me that says check while warm.

6 of one half a dozen of the other. Check it both warm and cold and average the readings.

This is why the dipstick has a range to indicate the amount of oil, not a specific mark to indicate the level.

YMMV
Because cold oil is more viscous. Right after an oil change, it doesn't flow well, and is coating the surface of lots of things. It will take a long time for cold oil to settle into the pan that the measuring stick dips into.

Warming the oil reduces its viscosity, making it much easier to flow, and reducing substantially the amount of oil film that clings to all of the surfaces, allowing it to flow into the pan. Like the difference between maple syrup from the fridge, vs. hot.

The easy way to warm the oil is to run the engine.

After warming up the engine, then shutting it off, it still needs some time for the, now less viscous, oil to drain back into the pan. They say wait at least 5 minutes because by then the vast majority of the oil that is going to drain into the pan has done so.

I didn't re-read this thread, but I agree with the poster who suggested that 12 hours or 36 hours count as more than 5 minutes, and measuring the oil cold after a long time, satisfies the directions (assuming the engine has been run since the oil change).
 
Yes, they didn't explicitly say that the oil should be warm but if they didn't want it to be warm why would they say to start the car and wait at least 5 mins after shutoff
See post #49, the manual does explicitly say that the engine should be at normal operating temperature, so yes, warm oil. And oil does expand when it warms up so a cold oil reading will be different.

But if owners think they know better than the factory, they can do whatever the heck they want. Afterall, I’m not making their car payments…
 
See post #49, the manual does explicitly say that the engine should be at normal operating temperature, so yes, warm oil. And oil does expand when it warms up so a cold oil reading will be different.

But if owners think they know better than the factory, they can do whatever the heck they want. Afterall, I’m not making their car payments…

Why not run your own test, if you believe your interpretation? Others have already done so and concluded that there is no difference between the readings cold, or after 5 minutes of being shut off. I know I have.
 
If you start the engine to check the oil, and it's low, haven't you possibly damaged the engine?
 
Why not run your own test, if you believe your interpretation? Others have already done so and concluded that there is no difference between the readings cold, or after 5 minutes of being shut off. I know I have.

I've compared both readings, and my own findings are in line with others who have compared. That is, that there is about 1/6" to 1/8" difference between readings. Whether that is significant or not is up to the owner of the car with the engine specified, which is the 2.5T.

Speaking for myself, I take the word of the Mazda manual writer, who works in conjunction with Mazda engineers, over anyone with 20, 30, 40 years of experience doing their own oil changes on different cars. No disrespect intended. Scotty Kilmer (a YouTube content creator) is a great example of someone with a ton of experience, who can still get things wrong sometimes. I don't mean to imply that you're wrong - the point of what I'm trying to say is that according to the manual/Mazda, the right (or most accurate) way to check the level is when the engine is warm, not when it's cold.
 
Why not run your own test, if you believe your interpretation? Others have already done so and concluded that there is no difference between the readings cold, or after 5 minutes of being shut off. I know I have.
I have done so, and I find a 2-3 mm difference. As I clearly stated I don’t care what you do, I don’t make your payments. But new owners should know exactly what Mazda recommends, then make up their own minds.

This thread reminds me of the ubiquitous engine break-in threads. Everyone has their opinion.
 
I have done so, and I find a 2-3 mm difference. As I clearly stated I don’t care what you do, I don’t make your payments. But new owners should know exactly what Mazda recommends, then make up their own minds.

This thread reminds me of the ubiquitous engine break-in threads. Everyone has their opinion.
Interesting, I've done this experiment a few times. I got home and waited exactly 5 minutes and checked the level. Then, I got up the next day and read it again. It was roughly 1mm higher. I checked it again a week or so later and noted about the same. If you think a 1-3mm difference is something that will be detrimental to an engine's life, you may have OCD. Either way, it in no way makes a bit of difference.

Have fun living with your stop watch! :)
 
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