2003 Subaru Outback EZ30, Napa 5W30 Hi-Mileage Synblend, 4417 miles

Jan 4, 2019
Levittown, PA
Analysis for my new-to-me daily driver. 2003 Subaru Outback LL Bean, EZ30 H6. Napa 5W30 High-Mileage Synthetic blend. Supertech ST9688 filter. No change in oil level throughout the interval.

Ran for 4174 miles and looking at the TBN I'm glad that's all I ran it. Used this oil twice for runs about this long, this was the first analysis I did. For the fuel dilution I'm thinking it maybe because of the cold winter, I was letting the car run to warm up a bit on the cold mornings. Didn't seem to hurt the viscosity though unlike the GDI V8 in my previous GMC daily driver.

One other small detail, this was five quarts of SP-rated oil and one quart of SN+-rated oil.

Changed for MAG1 10W30 synthetic with a Bosch 3312 filter and I'll get that analyzed around the same interval. If it's still diluting I'll try and track down the cause. Not planning long intervals on this car so far, I am planning analysis at least every other change to keep an eye out for coolant from the water pump buried in the timing cover.

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