I could be wrong, but I thought I read or heard somewhere that teflon was a powder. Someone mentioned those particles were gonna clog up your filter. I also heard that the temperature required before the teflon even "bonds" with metal...would be so high that engine damage would result from those high temps. But again, I could be mistaken. And a question on synthetic oil...has anyone successfully switched to synthetic on semi-high mileage cars, without developing oil leaks? I'm not sure about Honda...but the VW's and Audis I work on...if the owner wants synthetic..he has to start using it before the engine is broken in, or it leaks EVERYWHERE. I thought of going to synthetic myself...but not if my engine will start leaking.