changing your oil

The oil's color is my 'trigger'.

The 318 in my daily driven Dart uses quite a bit of oil because of worn valveseals, but I'm also running a thin oil.
So I only replenish it once a while with a pint of new oil.
As long as the oil maintains its dark brown semi-transparent color this way, I see no reason to change it.

My other (all garaged) cars hardly see any roadtime so the oil in their engines can be in there for a good number of years.