Overfilling Engine Oil

I forget exactly what the owners manual for my '16 Nissan Versa says the oil capacity is but it's something like 3.625 or 3.875 qts if I recall correctly. I routinely put 3.17 quarts in and it still shows approximately 1/8" above the full mark. I have in the past added maybe 4 oz. more than needed on some of my previous engines when adding oil after there has been some consumption. I've never intentionally put 5 quarts in an engine that called for 4.5 quarts although I doubt it would hurt anything.
 
My 2018 Toyota Camry calls for 4.8 quarts. I dump in a 5 quart jug and go. No problems. The manual on my 1991 F-150, (5.0 V-8) calls for 6 quarts. But that shows WAY overfilled on the dipstick. So I fill with 5-1/2 quarts. Which takes it just over the "FULL" mark. Again no problems in 30 years of driving.

I don't think this matters much either way. I constantly hear about engines being destroyed by overfilling with oil. But I have yet to actually see one that this has happened to. My guess is you would get a lot of warning before it caused any real damage.

I put this into much the same category as shooting 5.56 MM in a .223 chamber. Everyone say's DON'T! But I have never seen or heard of any damage directly caused from doing either.
 
I could see that, but did he say how much it was overfilled by?
It's a little tough for me to remember the exact scenario, but it goes something like this. 1/2 quart seems to be the amount.

The N* was one of the early engines with a "high capacity" oil pan. This was done because the engine was mounted transversly and it was designed to pull at least one G in the corners (even more for the Pontiac GTP). So I think it held 6.5 quarts (but it could have been 7.5 quarts)
At any rate the mechanics would almost always put in 7 (or 8, if the latter is true). So 1/2 quart.
The engine oil level was also supposed to be checked HOT, (it's in the manual) which the mechanics did not do, so due to thermal expansion the end result was over a HALF quart overfull.
 
I just put in the volume the manufacturer specifies (which puts the level about 90% of the way from low mark to full mark, checking it cold). Easy!
That means my container of leftovers grows by about 0.6 (5-4.4) quart each time, so theoretically after 7 or 8 oil changes, I won't have to buy oil for the next time.
 
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the only engine I know of where this would cause problems was the Chrysler 16 valve 4cy on the Neon's, it would aerate the oil and cause lifter collapse. They took a long time to purge and made a heck of a clatter. On that one 1/2 quart low was about optimum.

Rod
 
I add what I know is about 1/2 qt short when I do an oil change.
I bring it to the full line by checking the level in the morning and adding a cup at a time in the days after.
I combine the leftovers into one jug.
The current one has PYB 5w-30, QSGB 10w-30, Havoline 5w-30 and ST synth 5w-30, enough to cover the next change.
 
If it's .5 qts or less, I stop at .5. If it is over .5 qts, I round up to the next full qt.

4.3 gets 4.5
5.5 gets 5.5
6.7 gets 7

But to answer your question, I don't think it matters at all.
 
IMO a tiny bit over the full mark is not really overfilled, but I would never knowingly add 1/2 quart or more over full. A couple times over the years, I pulled the drain plug for a few seconds to bring the oil level down into the safe zone, saving the drained oil of course. (Now I simply take care how much I add, and this is no longer necessary lol.) I prefer to keep the oil level somewhere in the middle between the marks... I am fortunate to have vehicles that never lose any oil to leaks or consumption so it always stays there.
 
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