That's a holdover from the old days when manufacturers used "sand casts" for the motor parts. The process is much better these days, I hope. I tend to change my oil @ 3000 mile intervals. Today's filters are much better also. As far as oil, I usually use Pennzoil full synthetic in all my vehicles with the Motorcraft filters. ( All my vehiles now use the same filter, 820S.) Sometimes Mobil1 or Valvoline if they have a good sale price.