I’ve had 2 vehicles improve long term running seafoam in the sump. My Lexus came to me (3.5v6) with what almost sounded like pin slap, young at 71k miles. About 15k miles later, it is definitely quieter. That said, I don’t run the prescribed 0-20 in it - it’s been 5-30 most of the time with half can of seafoam. Just 2 weeks ago it got its first 5-20 from my hands with a little 10-30 to meet the full mark (Mobil 1). It’s a little chattier on 5-20. No seafoam this go-round, but it no longer has that pin slap knock/ring.