Oil Level too high

Actually yes. If it's high enough that the crank counterweights are dipping into the oil in the sump, it whips it up into a nice froth which doesn't lubricate near as well as straight oil. A half quart or so over usually (note the word usually) isn't a problem but overfilling in general is a bad practice.

nate

To simplify oil changes, & allow easy remedy of overfilling, replace your messy drain plug with a fumoto drain valve. Oil changes have never been so easy. Well worth the $$.

-Jeff Deeney-

snipped-for-privacy@rogers.com asked:

I've just been searching for information on this question myself because the dealer overfilled the the engine oil on my new Subaru Forester. From :

An overfull oil pan may lead to oil leakage through the pan gaskets and seals. Excess oil also can contribute to higher pressures and excessive vapors in the engine crankcase. If the oil level is extremely high, the rotating crankshaft may strike the oil and cause the engine to labor harder.

And from :

Adding too much oil can overfill the crankcase. As the crankshaft spins around, it can whip the oil into foam if the level is too high. This, in turn, can cause a drop in oil pressure and loss of lubrication to critical engine parts. Also, too much oil may cause leaks as the extra oil is forced past seals and gaskets.

In my case, the oil is 9/16 inch above the "full" mark, which is about

2/3 of the distance between the "full" and "oil low" marks. Hopefully this is not enough to cause the crankshaft to strike the oil. I've driven the vehicle 40 miles without observing any oil leakage. Since this is a long weekend, I'll have to wait until tomorrow to find out whether the dealer is willing to drain the exess oil. Kenneth Almquist

Nate summed it up quite well.

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--- Bror Jace