Is the CX-5 Dip Stick Calibrated for Hot Oil temp? It would explain a lot

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2020 CX-5 GTR
I have a new GTR and brand new to this forum. After putting a couple hundred miles on my new CX5 I decided to go over some of the fluid levels in the car- even though I have paperwork showing everything has been gone over at prep by dealer and looks good. When I wake up I check the oil using the dipstick. It read exactly on MAX line. I’m happy but then I read the manual section about checking your oil stating turn on the car and run it until normal operating temperature is reached, turn it off, wait 5 minutes or more and take reading on dipstick. I drive the car for 20 minutes and turn it off. Waited 15 minutes and my dipstick it is now showing level above MAX line.

I saw a few post here that state that their initial oil fill on new CX-5 had dipstick reading sometimes as low as midway between Min and Max. Some state that when changing oil that they need to add more oil than what the owner’s manual specifies in order to bring oil up to the MAX line.

I'm new here and new to CX5 but I might suggest that those CX5 delivered with less than full oil readings from factory may have possibly been filled below max and done so purposefully.

It would make sense that the CX5 dipsticks was calibrated to be accurate when oil levels were taken when hot. Manufacturers more and more are recommending hot readings with calibrated dipsticks because they know that oil expands or volume increases when oil is hot and presume most people don't want to wait around if on the road until car cools completely down to check their oil.

I believe this is the case with our CX5's. Otherwise the manual would not describe the process of checking the cars oil like it does. A few Google searches using phrases like 'are oil dipsticks calibrated for cold or hot oil" led me to many credible posts saying that yes - some manufacturers calibrate dipsticks to read accurately when engine oil is hot. Also saying that measurements taken when not hot will not be accurate on a dipstick calibrated for hot readings,

Getting back to what I personally observed I can concur completely with this. MAX line on cold morning reading and noticeable above MAX line when using the recommended oil check procedure in CX5 owner’s manual.

I called the dealer and asked if mine had been raised to max from the initial level delivered by Mazda Japan. The service writers emphatically said ‘no- he has been there 8 years and never seen anyone modify oil levels when checking in a new vehicle. So I said, to be sure you’re telling me that what is in my car was done at factory and no one messed with it. He said yes. That still doesn’t make me feel comfortable on any level –maybe because it is coming from a service writer at a dealership.

FWIW, if my thinking is correct, a lot of the DIY oil change posts here are getting things wrong. They may acctually be overfilling. Max on a cold fill should be lower than MAX. Maybe just putting in what MAZDA says is the right capacity for your engine is where you should be filling your oil regardless of whether it hits MAX on the dipstick or not. Maybe one of you could kindly verify this if after you fill your sump to what is seemingly low level. I'd appreciate it if you would then check it following guidlines in the owner's manual. I would like to know what you find - specifcally if you get a hot reading at the MAX line . I will not happy knowing I have been breaking in my new car with an oil overfill.

So I will call Mazda corporate tomorrow to get a straight answer for ‘Is the CX-5 calibrated for hot oil or cold oil temperature.” I’d also like to make sure the GTR has a different dipstick than the non-turbo since it states it has a slightly larger capacity. If any of you have a good contact number let me know.
 
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I have a new GTR and brand new to this forum. After putting a couple hundred miles on my new CX5 I decided to go over some of the fluid levels in the car- even though I have paperwork showing everything has been gone over at prep by dealer and looks good. When I wake up I check the oil using the dipstick. It read exactly on MAX line. I’m happy but then I read the manual section about checking your oil stating turn on the car and run it until normal operating temperature is reached, turn it off, wait 5 minutes or more and take reading on dipstick. I drive the car for 20 minutes and turn it off. Waited 15 minutes and my dipstick it is now showing level above MAX line.

I saw a few post here that state that their initial oil fill on new CX-5 had dipstick reading sometimes as low as midway between Min and Max. Some state that when changing oil that they need to add more oil than what the owner’s manual specifies in order to bring oil up to the MAX line.

I'm new here and new to CX5 but I might suggest that those CX5 delivered with less than full oil readings from factory may have possibly been filled below max and done so purposefully.

It would make sense that the CX5 dipsticks was calibrated to be accurate when oil levels were taken when hot. Manufacturers more and more are recommending hot readings with calibrated dipsticks because they know that oil expands or volume increases when oil is hot and presume most people don't want to wait around if on the road until car cools completely down to check their oil.

I believe this is the case with our CX5's. Otherwise the manual would not describe the process of checking the cars oil like it does. A few Google searches using phrases like 'are oil dipsticks calibrated for cold or hot oil" led me to many credible posts saying that yes - some manufacturers calibrate dipsticks to read accurately when engine oil is hot. Also saying that measurements taken when not hot will not be accurate on a dipstick calibrated for hot readings,

Getting back to what I personally observed I can concur completely with this. MAX line on cold morning reading and noticeable above MAX line when using the recommended oil check procedure in CX5 owner’s manual.

I called the dealer and asked if mine had been raised to max from the initial level delivered by Mazda Japan. The service writers emphatically said ‘no- he has been there 8 years and never seen anyone modify oil levels when checking in a new vehicle. So I said, to be sure you’re telling me that what is in my car was done at factory and no one messed with it. He said yes. That still doesn’t make me feel comfortable on any level –maybe because it is coming from a service writer at a dealership.

FWIW, if my thinking is correct, a lot of the DIY oil change posts here are getting things wrong. They may acctually be overfilling. Max on a cold fill should be lower than MAX. Maybe just putting in what MAZDA says is the right capacity for your engine is where you should be filling your oil regardless of whether it hits MAX on the dipstick or not. Maybe one of you could kindly verify this if after you fill your sump to what is seemingly low level. I'd appreciate it if you would then check it following guidlines in the owner's manual. I would like to know what you find - specifcally if you get a hot reading at the MAX line . I will not happy knowing I have been breaking in my new car with an oil overfill.

So I will call Mazda corporate tomorrow to get a straight answer for ‘Is the CX-5 calibrated for hot oil or cold oil temperature.” I’d also like to make sure the GTR has a different dipstick than the non-turbo since it states it has a slightly larger capacity. If any of you have a good contact number let me know.
In my case with SkyActiv-G 2.5L, there’s almost NO difference when I measure the oil level more than 5 minutes after the engine been shut off, or measure the oil level the first thing in the morning before the engine start, with Mazda moly 0W-20 oil. There’re several here with 2.5L who bothered to do the same test and they also got the same result like me. Not like ATF, engine oil expansion rate due to the temperature is minimum. Hence when you check the ATF level you have to do it at specified temperature, 122°F / 50°C In Mazda’s case, but not on engine oil. You may be thinking that when you measure the engine oil hot, the level should be higher due to the thermal expansion. But if you wait for the oil been drained back to the oil pan over-night, you also get more oil to raise the level. These 2 factors basically cancel out each other and the oil level measured in hot and cold conditions would be very similar.

From my personal experience, several brand new CX-5’s I’d checked with 2.5L, all were lower than FULL / MAX mark on oil level. Several members here also confirmed this. But based on several members here with 2.5T, they found the oil level was higher than MAX mark on their brand new CX-5.

The bottom line is for the SA-G 2.5L, if we pour in 4.8 quarts of fresh oil like Mazda specified in the manual during the oil change, we’d get about at ½ level between ADD and FULL marks; 5 quarts get you about at ⅔ level; 5.3 quarts get you at FULL mark of the dipstick no matter you check the oil hot or cold. There’s no way you put 4.8 quarts, or 5.1 quarts of 5W-30 oil in your case, and get oil level at FULL mark even if you measure it hot. The dipstick calibrated for hot readings on CX-5 simply is incorrect.

There’re more stories on under-filled fluids from factory on CX-5. Engine oil on 2.5L、engine coolant、automatic transmission fluid、and rear differential gear oil.

Now, a lot of the DIY oil change posts here are getting things right.
 
It honestly doesnt matter I dont believe. 5 quarts, new filter, dont worry about where it is. Worry if it moves.
But you do lose the safety margin if you don’t fill your oil to the FULL / MAX mark. I’d have lost my engine and got stranded on the highway with my Toyota Yaris iA due to the slow leak at the drain plug after the oil change by a Toyota dealer had they not overfilled the oil as usual.
 
But you do lose the safety margin if you don’t fill your oil to the FULL / MAX mark. I’d have lost my engine and got stranded on the highway with my Toyota Yaris iA due to the slow leak at the drain plug after the oil change by a Toyota dealer had they not overfilled the oil as usual.
The safety margin is engineered in. It's well over a quarter of a quart, and a low oil light is provoked when you approach it.
 
In my case with SkyActiv-G 2.5L, there’s almost NO difference when I measure the oil level more than 5 minutes after the engine been shut off, or measure the oil level the first thing in the morning before the engine start, with Mazda moly 0W-20 oil. There’re several here with 2.5L who bothered to do the same test and they also got the same result like me. Not like ATF, engine oil expansion rate due to the temperature is minimum. Hence when you check the ATF level you have to do it at specified temperature, 122°F / 50°C In Mazda’s case, but not on engine oil. You may be thinking that when you measure the engine oil hot, the level should be higher due to the thermal expansion. But if you wait for the oil been drained back to the oil pan over-night, you also get more oil to raise the level. These 2 factors basically cancel out each other and the oil level measured in hot and cold conditions would be very similar.

From my personal experience, several brand new CX-5’s I’d checked with 2.5L, all were lower than FULL / MAX mark on oil level. Several members here also confirmed this. But based on several members here with 2.5T, they found the oil level was higher than MAX mark on their brand new CX-5.

The bottom line is for the SA-G 2.5L, if we pour in 4.8 quarts of fresh oil like Mazda specified in the manual during the oil change, we’d get about at ½ level between ADD and FULL marks; 5 quarts get you about at ⅔ level; 5.3 quarts get you at FULL mark of the dipstick no matter you check the oil hot or cold. There’s no way you put 4.8 quarts, or 5.1 quarts of 5W-30 oil in your case, and get oil level at FULL mark even if you measure it hot. The dipstick calibrated for hot readings on CX-5 simply is incorrect.

There’re more stories on under-filled fluids from factory on CX-5. Engine oil on 2.5L、engine coolant、automatic transmission fluid、and rear differential gear oil.

Now, a lot of the DIY oil change posts here are getting things right.
Want a picture before I leave work? 5 quarts, new filter. She full bro.
 
The safety margin is engineered in. It's well over a quarter of a quart, and a low oil light is provoked when you approach it.
In my case the low oil pressure warning light had never come on, but I lost more than 3 quarts of oil counting the overfill. It took 2 quarts to reach only ⅓ between ADD and FULL. The total oil capacity is 4.5 quarts but that’s again from Mazda’s specs. I certainly wouldn’t want my engine running with less than half of the oil for long even if the oil pressure warning light isn’t on!
 
You really don’t know how much oil your Mazda dealer had actually put it in, do you?
Yes, they put in the 5 quart jug I bring them. No more, no less. I didnt verify the manufacturer's advertised measurements of the jug vs actual content though, but I bet it’s close.
 
In my case the low oil pressure warning light had never come on, but I lost more than 3 quarts of oil counting the overfill. It took 2 quarts to reach only ⅓ between ADD and FULL. The total oil capacity is 4.5 quarts but that’s again from Mazda’s specs. I certainly wouldn’t want my engine running with less than half of the oil for long even if the oil pressure warning light isn’t on!
And the issue was a mechanical failure, not +- a fractional amount of oil. This is being way over analyzed.

 
I saw a few post here that state that their initial oil fill on new CX-5 had dipstick reading sometimes as low as midway between Min and Max. Some state that when changing oil that they need to add more oil than what the owner’s manual specifies in order to bring oil up to the MAX line.

I'm new here and new to CX5 but I might suggest that those CX5 delivered with less than full oil readings from factory may have possibly been filled below max and done so purposefully.

I would agree that it is done purposefully. The oil level is not "low" if it is within the MIN/MAX range. Keeping the oil level at the MAX mark is simply a matter of preference - some like to keep it as full as possible for "just in case" scenarios like yrwei52 mentioned.

EDIT: I reread your post and got a bit confused initially. After reading it again, it does sound like your oil may have been overfilled. I don't know if the amount is enough to cause any damage, but I understand the concern. Keep us posted as to what Mazda Corporate says.
 
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I have done 2 oil changes on my 2019 GT-R. Both times with new filters and letting the hot oil drain for at least an hour.

In both cases it took 5.5 quarts to reach the max line on the dipstick and that included pre-filling the filter with several ounces of the 5.5 quart total.

If I check my oil level within a half hour of driving or check it in the morning cold, on a flat level garage floor, the difference in the level on the dipstick iis maybe 1/16". Not enough to even be slightly concerned about.

My car only has about 8000 miles on it and I have not noticed any consumption so far. If it ever does start using oil I will add oil until it hits that top mark again and sleep easily.
 
Yes, they put in the 5 quart jug I bring them. No more, no less. I didnt verify the manufacturer's advertised measurements of the jug vs actual content though, but I bet it’s close.
Not sure how it’s possible that you can get your oil level to the MAX mark with only 5 quarts of oil, when Mazda’s specs say 5.1 quarts on oil capacity for your 2.5T.
 
And the issue was a mechanical failure, not +- a fractional amount of oil. This is being way over analyzed.

My point is when we have our oil level at FULL / MAX mark, we’ll have more safety margin in case something happens including the oil consumption issue. But I agree this thing is being over analyzed. And the inconsistent or inaccurate “approximate fluid capacities” by Mazda has created more issues.
 
My Subaru had two MAX levels, one for cold and one for hot. 2010. Ed
I checked the 2010 Subaru Forester owner’s manual. There’re 3 marks on the dipstick:
1) Notch
2) Upper level
3) Lower level

And
“• Checking the oil level
Check the engine oil level at each fuel stop.
1. Park the vehicle on a level surface and stop the engine.
2. Pull out the level gauge that has the “ ” symbol on top, wipe it clean, and insert it again.
3. Be sure the level gauge is correctly inserted until it stops.
4. Pull out the level gauge again and check the oil level on it. If it is below the lower level, add oil to bring the level up to the upper level.”

“If you check the oil level just after stopping the engine, wait a few minutes for the oil to drain back into the oil pan before checking the level.
Just after driving or while the engine is warm, the engine oil level reading may be in a range between the upper level and the notch mark. This is caused by thermal expansion of the engine oil.

To prevent overfilling the engine oil, do not add any additional oil above the upper level when the engine is cold.”

So it’s very clear that when you check the engine oil level cold, use the “Upper level” mark for full oil level.

853522C1-0B90-4FE8-9473-3A781637FBFF.jpeg
 

EDIT: I reread your post and got a bit confused initially. After reading it again, it does sound like your oil may have been overfilled. I don't know if the amount is enough to cause any damage, but I understand the concern. Keep us posted as to what Mazda Corporate says.
As I said in my previous post, based on several members here with 2.5T, they found the oil level was higher than MAX mark on their brand new CX-5. So this’s not a surprise.
 
I'm surprised people who DIY are filling to the max level on the dipstick.
I have NEVER filled to the max level. I see no need. Why would you do this?

I figure out how much oil is needed to get the oil level to the midpoint of the dipstick (or just above), and use that amount every time.

I've never had a problem doing this with multiple vehicles, each driven between 150K-190K miles.
 
I think in the previous incarnation of this thread someone pointed out the fill might be liters, not quarts. Liters are slightly bigger than quarts.
 
I have done 2 oil changes on my 2019 GT-R. Both times with new filters and letting the hot oil drain for at least an hour.

In both cases it took 5.5 quarts to reach the max line on the dipstick and that included pre-filling the filter with several ounces of the 5.5 quart total.

If I check my oil level within a half hour of driving or check it in the morning cold, on a flat level garage floor, the difference in the level on the dipstick iis maybe 1/16". Not enough to even be slightly concerned about.

My car only has about 8000 miles on it and I have not noticed any consumption so far. If it ever does start using oil I will add oil until it hits that top mark again and sleep easily.
Thanks for reporting your experience. It proves again Mazda’s approximate oil capacity on 2.5T with 5.1 quarts is less than common knowledge where the oil capacity is based on the oil level at the FULL / MAX mark.

Mazda stated this in the owner’s manual about oil level checking:

“If it is near or below MIN, add enough oil to bring the level to MAX.“

So why don’t we put enough oil to the FULL / MAX mark at oil change, but add enough oil to the FULL / MAX mark when the oil level is low? Why is the inconsistency about this?
 
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