@jent, I made my report(s) a little easier to look at for comparison. I'm using 5W-40 Pennzoil Platinum. Just a quick glance, your aluminum numbers are better than my last report (6,786 miles compared to your 7,466 miles). Your Iron numbers are much higher than mine. And your viscosity is low (11.29 compared to my 12.4). The viscosity range for 5W-40 is 12.5 - 16.3.
At this time, I feel pretty comfortable running 6,000-mile drain intervals. Keep in mind, a lot of my miles are towing miles. Outside of high aluminum numbers, I'm fairly content with my reports. Regardless of the oil used, high aluminum numbers seem to be normal for this engine. I wish we could see a few high mileage (100,000+ miles) UOA reports to predict what trends might look like. Eventually, we'll see a high mileage engine torn apart to know where the weak links are in the engine.
Lube Time: 4,133 miles
Unit Time: 4,133 miles
Lube Time: 3,551 miles
Unit Time: 7,684 miles
Lube Time: 5,123 miles
Unit Time: 12,807 miles
Lube Time: 6,786 miles
Unit Time: 19,593 miles
Wear Metals
IRON: 19, 21, 26, 26
CHROMIUM: 1, 1, 1, 1
NICKEL: 0, 0, 0, 0
ALUMINUM: 13, 13, 25, 26
COPPER: 14, 7, 5, 3
LEAD: 0, 0, 0, 0
TIN: 0, 1, 1, 0
CADMIUM: 0, 0, 0, 0
SILVER: 0, 0, 0, 0
VANADIUM: 0, 0, 0, 0
Contaminant Metals
SILICON: 36, 13, 12, 13
SODIUM: 4, 3, 1, 4
POTASSIUM: 24, 14, 26, 13
Multi-Source Metals
TITANIUM: 0, 0, 0, 0
MOLYBDENUM: 47, 84, 60, 94
ANTIMONY: 0, 0, 3, 0
MANGANESE: 5, 2, 1, 1
LITHIUM: 1, 0, 1, 0
BORON: 72, 169, 78, 169
Additive Metals
MAGNESIUM: 21, 877, 177, 1054
CALCIUM: 2505, 1703, 2772, 1738
BARIUM: 0, 0, 0, 0
PHOSPHOROUS: 803, 888, 977, 943
ZINC: 920, 1046, 1141, 1088
Contaminants
FUEL DILUTION: 0.6%, 0.1%, 0.6%, 0.5%
SOOT: <.1, <1, <1, <1
WATER: <.1, <1, <1, <1
Fluid Properties
VISCOSITY 100 *C: 13.0, 12.6, 12.9, 12.4
BASE NUMBER: 8.32, 9.52, 6.84, 8.09
OXIDATION: 9, 10, 10, 10
NITRATION: 10, 10, 10, 11