I'll run either Fram Ultra or Mobil 1 oil filters for 2 OCI's. This can be 10,000-16,000 miles of total use. All my vehicles are bought new and well maintained from new so there is no "mysterious" past maintenance history. The two older vehicles the oil filters are a major pain to access. With the new vehicle the oil filter is fairly easy to access but it makes a royal mess when it's changed. I've been buying Mobil 1 oil and the Mobil1 oil filter during their rebates. The Mobil 1 oil filters only costs $5 with the rebate if I purchase it from Walmart with the Mobil 1 oil. Walmart is the least expensive for both. As previously mentioned there is oil left in the engine that doesn't get drained out so the little bit of oil left in the filter is adding minuscule old oil to the new oil.
Whimsey
Whimsey