This was Wrexy’s first UOA. Mine too.
In the first 80,000 miles, oil changes were at the recommended 7,500 mile intervals, at the dealership, using Subaru Oil, or Mobil 1 or Pennzoil Platinum provided by me, and using the Subaru filter.
102,000 miles on the car. The engine is stock.
5000 miles on the oil. The final miles were on a quick round-trip to California, pulling 6-percent-plus grades at 75 mph in 104-degrees heat, with the air conditioning maxed.
Oil filter was a Fram Ultra XG7317. I will post pictures of the filter in that section.
I was interested in:
1. Signs of wear from the hot operation.
2. Is there “shearing” or fuel contamination of the oil?
3. The oil filter is longer than the specified one and there have been some concerns about “coking” of the oil due to close proximity of the filter to hot exhaust.
Oil that went in is Pennzoil Ultra Platinum 10W30. I’m thinking of comparing the shearing results, duplicating the driving conditions as best I can. Filter that went in is a Fram Ultra XG6607.
I was expecting to get fuel-dilution results. It was my reason for going to this tester. They don’t appear to have done this test and I’m disappointed.