Dealers consistent overfill oil.

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You need to check the oil level on a hot engine a few minutes after shutting off before the oil drains from the oil system to the sump.
 
Originally Posted by hallstevenson
Originally Posted by Mike L. V.
Well you're probably correct. I was very generous in my estimate. More likely dealerships are doing 60 second dump and pumps.

Don't worry, there's folks here who let it drain overnight and are convinced it's "the right way" !!
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You for that right ^^^^^^^^
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Originally Posted by Ded Mazai
You need to check the oil level on a hot engine a few minutes after shutting off before the oil drains from the oil system to the sump.

What vehicle(s) says to do it that way ?
 
Originally Posted by Ded Mazai
You need to check the oil level on a hot engine a few minutes after shutting off before the oil drains from the oil system to the sump.

Wouldn't this give a false reading. I check mine in the morning so I don't have to mess with wiping it off, for some reason on my Lucerne it's to hard to read if you pull it out wipe it off and stick it back in, when you pull it out it has oil all over it and is hard to tell exactly where it's at.
 
I usually drain my own oil and do it on a cold engine while all the oil is in the pan from sitting from overnight. I pull the plug let it drain until it starts dripping then screw the plug back in a couple turns to let oil on the side of the pan drain while I change the filter. By the time I've changed the filter no more than an or two oz. has accumulated when I pull the plug back out and drain until a slow drip before putting the plug in tightening it and refilling the sump. I forget which the owners manual calls for 3.5 or 3.7 qts. but when I checked on the internet it said 3.2 qts which would make since since the car is Japanese and they probably consider 3 liters as a complete fill. Even filling with 3.2 qts the level on the dipstick shows slightly above the full mark. I'll bet if I took it to a fast lube place most of them would fill it with 4 qts. since this is what most 4 cylinders call for.
 
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The best way to ensure the job is done right is to do it yourself. I get the sense that this may not be possible in your situation. 8-10mm is not the end of the world in my opinion.

It's more important that they reinstall the drain plug correctly and tight and that the filter is on properly.

My guess on the overfill is that they don't drain the old oil completely in order to save time. Once the oil has slowed to a trickle they put the plug back in. Most of us that change our own will let it drain completely.
 
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You need to check the oil level on a hot engine a few minutes after shutting off before the oil drains from the oil system to the sump.


This is an interesting thought, but a "few minutes" would actually mean that the oil has indeed drained back into the pan except for the small amount that MIGHT be trapped in oil passages and filter.

An oil pump in an engine pumps probably 6-12 GALLONS PER MINUTE, It likely takes a second or two for the oil in, say the valve covers, to drain back down into the sump at operating temperatures.
 
If oil changes were done to Bob is the Oil Guy standards:

Customer: Hey! When's my car going to be finished!?

Pimply "tech": Uh, sir...do you have another way to get home? Your car's going to need to drain for like twelve or thirteen more hours.
 
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