ORIGINAL: proanti1
Why use ATF? Its basically hydraulic fluid, I know from experience that it damages certain plastics and rubbers, dunno what it would do to a filter element though. Probably not the safest thing to have around an rc car.
I've been using it for six years and a schmidge over three gallons and haven't hurt a single part on my engines. IT doesn't eat the foams, it doesn't eat the boots, and it traps the dirt nicely.