I stopped by an AutoZone to pick up some brake fluid for the ST and pretty much all the DOT4 brands were synthetic. Maybe it's something I hadn't noticed before. Is it OK to use synthetic brake fluid? I don't really care for the Honda brake fluid but is it synthetic or conventional? I bought some Honda brake fluid at a dealership once and the foil seal had come undone and the fluid had a weird color to it so I tossed it.