I have a 2016 Toyota RAV4 hybrid with 2.5 liter engine that takes 4.4 liters of oil (with filter; without filter it's 4.0 liters). The difference between "low" and "full" oil level is 1.5 liters, so the "low" level is 2.9 liters. I have noticed that when servicing the car at the dealership, they consistently put too much oil every time. The car consumes no oil, so the overfill remains continuous.
I estimate the excess to be approximately 15% of the "low"-"full" difference, which is approximately 5% of the full capacity, or approximately 0.2 liters.
Can it damage the engine if there's 5% too much oil all the time in the engine? So far, I have driven 50 000 km and the engine still works just fine, even though most of the time the oil has been overfilled by the same amount.
I always measure the engine oil level when cold on a level ground, although the car manual specifies to wait 5 minutes after stopping driving on a warm engine to measure the oil level. There are two processes that may work in opposite directions: different thermal expansion coefficients of oil and steel/aluminium mean the oil level at the dipstick when hot is higher than when cold (although it may not be as simple as that because the dipstick itself also experiences thermal expansion, but then again the dipstick tube would probably also expand by approximately the same amount), whereas oil dripping down to the oil pan from other parts of the engine mean the oil level at the dipstick when hot is lower than when cold. The processes work in opposite directions, but I'm not sure which of the two processes is more significant.
