I just got my oil analysis back for my car . I have a 02 outback base wagon with 32 k miles on it . I have had the car diagnosed with piston slap at 6k miles . I use mobil 1 5w40 in the winter and 10w40 in the summer I change the oil at 5 k intervals . My oil came back normal for my engine . No abnormal wear due to the slap problem . So I guess SOA is right that it does no damage to the engine . I sent the oil to Blackstone labs . It cost 20 bucks and they supply the shipping container . Well I felt so good about my car that I gave it a good detailing to day at work . I now feel alot better and I'll just have to learn to live with the noise .
Mike