Here is the comment from the analysis lab. Any idea why the aluminum would be twice the expected value?
Bill
Comment: Universal averages show typical wear from this type of engine after a routine oil use of about 4,200 miles. Your oil was in use 5,000 miles, and we found wear from your engine at around average levels, with the exception of aluminum. Your aluminum, from pistons, is about double the average reading. All other wear looks normal, so we don't think this is showing a major problem, just something you may want to keep an eye on. No antifreeze, fuel, or water was found. We'll watch aluminum closely in the next sample.
EQUIPMENT MAKE: 2000 Ford Explorer
Mileage: 40,840
EQUIPMENT MODEL: 4.0L V-6
FUEL TYPE: Gasoline (Unleaded)
OIL USE INTERVAL: 5,000 Miles
OIL TYPE & GRADE: 5W/30 (gas)
MAKE-UP OIL ADDED: 0.25 qt