checking oil after driving vs cold engine

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in most cars it doesn't matter. however, i have a 3.5L V6 RAV4 that if engine oil is full when hot, it's going to be overfilled about 1.5qt when cold, say sitting overnight. I initially thought dealership was overfilling before figuring it up. Now, i try to change oil on cold engine (i get more old oil out) and fill it to the full line and later add up some more to account for oil in filter difference. alternatively, i fill it to low line if changed after engine running. if one topped it up after running, it would be overfilled later. ironically, the standard description in the car manual talks about checking oil after driving.

i suspect, the oil is hiding in VVT-i, that is huge because of 2 banks and both intake and exhaust valves regulated.
if one waits several hrs (ie overnight) that oil drains back to sump.

has anyone noticed anything like that?
 
I think in the owner's manual it states to check oil after car has warmed up, wait several minutes then check.
 
Dunno if you're only asking about the RAV4. Different machines have different recommendations.

I'd always checked cold, which seems a more sensible procedure to me because you eliminate a lot of potential variables.

I suspect manufacturers have moved to checking hot because people (and certainly garages) aren't prepared to wait (video generation, instant gratification, young people today...blah blah)

Caused a lot of trouble with the GF's scooter, which I checked and (slightly over) filled cold, hence giving the mechanic an opportunity to destroy my credibility and re-inforcing her faith in the Taiwanese procedure, which is not to check it at all, ever, because the Yamaha oil was installed by a Yamaha PROFESSIONAL and lasts forever.
 
i'm asking if anyone noticed a difference. RAV4 is the only car where i do see a difference. and i'm not talking about shrinking oil volume in cold. i'm talking about oil draining from VVT. that overnight drain is normal operation, BTW:

Quote:
Allow the oil to drain from the VTC system by not starting the engine for at least six hours.

http://www.autoserviceprofessional.com/article/92158/honda-cold-rattle
 
I see a difference with my Liberty. If I check it 5 minutes after shutting down it reads low, if I wait 10-15 mins it's pretty much dead on (not enough to make a difference) and after an hour, it's just like overnight.

I pretty much wait at least 15 minutes in all cases. Or more.
 
Doing many oil changes (the old fashioned way, including starting the car, checking for leaks/good gauge reading, shutting it down and checking oil before it goes out the door) on all different kinds of cars, if it's within 1/8 qt. of where I'd like it to be after sitting for 5 minutes it's good enough for me. Most of the vehicles (conventional pushrod, iron block, non-VVT/turbo powerplants) I've owned, I never noticed a difference in the level 10 mins. after shutoff vs. overnight, but a '99 Tahoe threw me for a loop a few months ago when I put in 5 qts. and it was showing nearly a quart over full. Having been around the Vortec 350 in dad's '97 Suburban (420K to-date and still humming along) plenty I chalked it up to the auxilary oil cooler this truck had on it draining back into the pan after a few minutes, and didn't pull the extra oil back out.
 
My Sedona's cartridge setup doesn't seem to utilize any drainback valve, and will actually read overfull if you give it a couple hours to cool and the oil to drain back to the sump. If I check when warm after a drive, like the manual says to, it's right where it should be.
 
On my 4th gen Maxima, there is a big difference between warm and cold oil levels, at least half a quart! And it takes a LONG time for the oil to reach operating temp! I'm using Edge 0w30

But on my previous car, an ES300, oil temp didn't matter at all.
 
Such variations indicate horrible industrial design. If a Toyota 3.5L engine actually shows a variation of 1.5L, which is beyond the resolution of the dipstick, it's quite possibly the worst designed oil pan and dipstick indicator system ever created.

I've seen occasionally up to 0.5qt differences, and that was really pushing it, and could possibly be user error (parking variations) to some extent. Most of our cars I've never seen any practical difference.
 
I see a difference in my Rav4 but not a 1.5qt difference. Maybe a 1/4 - 1/2 qt.
 
Cold vs hot should always make a difference. Oil needs to drain back from the head/heads.
 
I always check when it stone cold, or after 5 min shutting it down. Like on road trip, I like check the oil while filling up gas.
 
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