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· Three-pedal evangelist
2020 Premium 6MT
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1,853 Posts
Reading through this thread has certainly been interesting. Way back when I used to do my own oil and filter changes, I always added oil so the level would be somewhere between the add and full marks. Now that I have someone else do my oil and filter changes, I have noticed without fail, the oil is always filled slightly higher than the full mark. This does not matter whether it's a dealership, a local indy mechanic or a "quick lube" place. It's always slighter over the full mark - EVERY SINGLE TIME.

My speculation is that most facilities have pre-calibrated amounts of oil pumped in. 5.0 quarts even sounds like an amount from a bygone era where many crank cases held 4 quarts and a filter held a whole quart of oil. This would make sense at other than the dealership which should know each car and how much really should be added, but maybe they don't think a little more is really an issue. I have always read in the past that overfilling your crankcase can cause aeration and loss of oil pressure, but then how far would you need to overfill to have this actually happen? I doubt using 0.3 quart more (5.0 vs. 4.7) is really an issue. The OP's case seems like there was almost an extra quart of oil in his new car. Might this be because they expect some oil consumption during break-in?

On a side note, when I was growing up, my dad had a 1971 AMC Gremlin. If you filled the oil to the full mark on that car, it would burn off oil until it reached the add mark, then stay there. So we always filled it to slightly above the add mark. The car lasted 120K miles until it was totaled.
 
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