There's a running battle going on over in another newsgroup.
Whether to "change oil every 3000 miles" or Change oil when the "CHANGE OIL" light comes on. ( up to 10,000 miles between changes ? )
One side says; Motors are engineered to go longer between oil changes.
Others say; "Vast conspiracy to make engines wear out faster"
My car has the "Change oil" light, but I get nervous around
5000 miles, and change it anyway. ( oil still looks like new )???