Cooling system

(scratch)
How would you ever be able to check your oil at the gas station, or the mechanics at the service station?

Two examples of probably the worst times to expect an accurate reading! When I was a kid working in a gas station (back in the days of full service) I would often feel a little guilty selling a customer a quart of oil because his sump was "down a bit" after having rolled a mile down the hill from their suburban home and sat at the pump for five minutes.
 
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The manual on my Honda CR-V says check oil level at each fill-up, but be sure to wait a few minutes for oil to drain back to the oil pan.

Just go do the experiment. The oil level when cold should be (very) slightly higher than when engine is warm. Basically the instructions are emphasizing you have to wait a few minutes for oil to drain back after the engine is off to check the oil level. Then the difference on oil level between warm and cold engine won't be too much. But I like the way checking the oil level the first thing in the morning as I don't need to wipe the dipstick, and the oil level will be clearly shown on the mark at my first pull!

Meh, I find the exact opposite, you can wait 15 to 20 minutes after shut down then check it, I find my level is always higher. You do get a little expansion when the fluid is warm just like ATF but on a smaller scale, and while it's warm, 15 to 20 minutes is plenty of time for it to flow back into the pan, and 0w-20 flows faster when it's warm so there's no reason to doubt it's all down there by then.
 
Oil Level ⋯

Meh, I find the exact opposite, you can wait 15 to 20 minutes after shut down then check it, I find my level is always higher. You do get a little expansion when the fluid is warm just like ATF but on a smaller scale, and while it's warm, 15 to 20 minutes is plenty of time for it to flow back into the pan, and 0w-20 flows faster when it's warm so there's no reason to doubt it's all down there by then.
Next time when you change your oil, see how long it's going to take when the oil stops dripping from the drain hole ⋯

And do the same experiment check the oil level the first thing in the morning and compare. But I agree, either way should be fine as Mazda didn't even give us a correct oil capacity in the manual anyway. :)
 
Next time when you change your oil, see how long it's going to take when the oil stops dripping from the drain hole *

And do the same experiment check the oil level the first thing in the morning and compare. But I agree, either way should be fine as Mazda didn't even give us a correct oil capacity in the manual anyway. :)
I've done the comparison...how do you think I know it's higher when it's hot?
It takes longer to stop dripping from the drain hole when the oil is cold compared to when it's hot.
 
Oil Level ⋯

I've done the comparison...how do you think I know it's higher when it's hot?
It takes longer to stop dripping from the drain hole when the oil is cold compared to when it's hot.
For some reason paris1 and I have different experience on this than yours. This's not just for CX-5, but for every vehicle we've owned!

All DIYers should know we change oil when the engine is hot or at least warm for faster drain-out. Even on watery 0W-20 oil it will keep dropping for hours until the engine is getting cold.

Kedis82ZE8 drained oil on his CX-5 over-night, and he needed 5.3 quarts to get to the "Full" mark of the dipstick although the Mazda calls for 4.8 quarts on 2.5L.

It basically took 5.3 quarts to get get it exactly at the top dot. I must have really drained it out.

I've used 0W-30 synthetic in another car before but this 0W-20 seems almost like water...wow that stuff is thin.

I've changed oil in all of my cars for the last 25 years but I am always nervous the first time changing it in a new car. This is an easy one... and will be much easier with the Fumoto on there next time.
Nothing was overly tight. A little more spillage out of oil filter than I expected but not a biggie.
 
For some reason paris1 and I have different experience on this than yours. This's not just for CX-5, but for every vehicle we've owned!

All DIYers should know we change oil when the engine is hot or at least warm for faster drain-out. Even on watery 0W-20 oil it will keep dropping for hours until the engine is getting cold.

Kedis82ZE8 drained oil on his CX-5 over-night, and he needed 5.3 quarts to get to the "Full" mark of the dipstick although the Mazda calls for 4.8 quarts on 2.5L.

Well, how about that. I've notice differences in oil levels for every vehicle I've also driven, my stepdaughters and my 2 neighbors since using synthetics, and I've only noticed this with synthetic motor oils. So who's right? I don't really care, I don't lose sleep at night over 1/16th of a difference in oil levels, and to argue over it is really ridiculous. You could Google thermal expansion of oil and also get similar differences of opinions. Like I said before, if you're between a half and full, you're probably golden. I just go by the owners manual and what Mazda says, it's the ONLY opinion that matters when under warranty. I'll let you have the last word since you're probably not going to just let this go. Enjoy the day!
 
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Oil Level ⋯

Well, how about that. I've notice differences in oil levels for every vehicle I've also driven, my stepdaughters and my 2 neighbors since using synthetics, and I've only noticed this with synthetic motor oils. So who's right? I don't really care, I don't lose sleep at night over 1/16th of a difference in oil levels, and to argue over it is really ridiculous. You could Google thermal expansion of oil and also get similar differences of opinions. Like I said before, if you're between a half and full, you're probably golden. I just go by the owners manual and what Mazda says, it's the ONLY opinion that matters when under warranty. I'll let you have the last word since you're probably not going to just let this go. Enjoy the day!
So I guess you're the one putting in 4.8 quarts of fresh oil instead of 5 quarts or more for each oil change to prevent any over-fill problems, and putting in 0.48 quarts of gear oil into rear differential which is way below the fill hole? You'll follow Mazda's recommendation never change the ATF and brake fluid? When rear turn signal needs a replacement bulb, you'll try to find very rare (and wrong) dual-filament 7443NA bulb which costs about $30 each because the owner's manual says so?

BTW, I did say in my previous post that I agree with you either way, hot or cold, should be fine when we check the oil level. Just make sure to wait enough time to let oil draining back to the oil pan. And paris1 and I were suggesting OP checking the oil level in the morning which will get a perfectly readable dipstick as OP has a hard time taking a read.
 
Okay I waited 20 min and still could not get a clear reading. What am I doing wrong . Easy to read when engine is cold and the reading is from the crankcase . Why does the stick have oil all over it when warm and able to see a base line on the stick. 6500 miles and second change about 900 miles on the second change. I use a 0-20 on my chevy van and very easy to read. The stick is smooth ane easy read. The mazda stick has a rough surface and the oil is hard to find on the stick. So I will check it cold. jz.
 
Okay I waited 20 min and still could not get a clear reading. What am I doing wrong . Easy to read when engine is cold and the reading is from the crankcase . Why does the stick have oil all over it when warm and able to see a base line on the stick. 6500 miles and second change about 900 miles on the second change. I use a 0-20 on my chevy van and very easy to read. The stick is smooth ane easy read. The mazda stick has a rough surface and the oil is hard to find on the stick. So I will check it cold. jz.

Cold reading should be good enough as long as you're between half and full, don't over think it.
 
Thermal expansion will be insignificant. Check it cold in the morning, as suggested above.

Drain when warm. Just warm, not hot.
 
The only downside to hot is to take care not to get burned. Otherwise hotter is a better drain.
 
The only downside to hot is to take care not to get burned. Otherwise hotter is a better drain.
Yes. But I let engine cool down a bit, then drain the oil. We can always let the oil drain for longer period of time to achieve the same goal.
 
The only downside to hot is to take care not to get burned. Otherwise hotter is a better drain.

+1. All the contaminants are still suspended in the oil and haven't settled to the bottom of the pan, better chance of draining them out while it's hot.
 
Not getting burned is a lot more important than getting the last few percent of contaminants out of the engine.
 
The only downside to hot is to take care not to get burned. Otherwise hotter is a better drain.

That's why I'm glad I installed Fumoto valves. Yeah takes a bit longer to drain out but you save time by not needing to wait to cool down oil. When done down draining the oil filter is cooled off a bit by then. I use gloves that go up to my forearms to protect from drops.
 
I purchase extra oil and after draining I flush it with clean oil while it still draining. The close and fill.
 
That's why I'm glad I installed Fumoto valves. Yeah takes a bit longer to drain out but you save time by not needing to wait to cool down oil. When done down draining the oil filter is cooled off a bit by then. I use gloves that go up to my forearms to protect from drops.
But with Fumoto valve you actually prevent a complete drain as its thread portion is too long extended into the oil pan. A while ago a member took his pan down with the Fumoto valve and was surprised by how much oil left in the pan!
 
But with Fumoto valve you actually prevent a complete drain as its thread portion is too long extended into the oil pan. A while ago a member took his pan down with the Fumoto valve and was surprised by how much oil left in the pan!

True.
 
I did not have the heart to read this whole thead but share the frustration with the "stick creep". If you have a good eye you can read it on the stick when hot. Not a problem for me but the GF has difficulty with a hot stick, OK leave it at that. I think what is going on is that the stick gets contaminants or additives, something stuck to it that causes the oil to stick more or less to it. It also tends to creep up the stick a bit somehow. Not a technical explanation just a theory but I do KNOW this. If you clean the stick with some carb cleaner and scuff it up a bit with a scotch brite pad or such you will have way less trouble getting a hot reading.
This I know from operating a boat with a blown 502 that required daily oil checks. Cleaning the stick makes it much easier to read which is important if you have to contort, hang upside down and have someone hold your ankles to get at the stick in a tight boat engine compartment. I have often wanted to design an electonic level check that would cycle at each start. Two or four sensors (one front, rear and each side of pan) would provide and accurate level regardless of position. That would be a way cool addon for a boat engine, they can eat oil one day and not the next, remeber a high performance boat engine is often run at near WOT level for long periods of time. It would be similar load as to dragging a Winnebago up a long grade for 30 minutes at WOT., You know an engine is working hard when it gets 2.1 MPG.
 
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