I started SLICK on Mobil1 and quality filters like K&N or WIX after her first 1K miles. I use OE fluids in my AT and do a drain/fill once a year living in a warm/hot climate. Differential gets AMSOIL synthetic gear oil! I know what motors look like inside after using Dyno oil even doing frequent oil changes, it's called sludge! I'll never use anything but synthetic...stays cleaner and runs cooler!
Gary

 

I run synthetic in mine, bought it used so not sure what was ran before that. I'm not sure if it really needs it since I DD mine.