Something does not sound right. I don't know year you are talking about but I was thinking they did put dipstick back in them at some point. You should see the level at least above the "low" mark with engine cold. It will rise a little once up to temp but not more than 1/4" or so.

Drive it 20 miles, park on level surface with engine off, let settle for a few minutes. Level should be between marks. You will not get 3 more quarts out upon removal of filter.

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Jim