Bump for an old but unanswered question about FL-22 anti-freeze/coolant. I have been unable to get any substantive information about this coolant on the web so far. I notice that the level in the expansion tank has been slowly dropping since we got our 5 last year, but there is NOT a coolant leak into the engine (verified with many oil analyses). So, it must be slowly evaporating. We've moved since buying our 5 and now the nearest dealer is ~150 miles away. I need some info about FL-22 so I know whether I can use a substitute to top off the expansion tank. Anyone?