I bought a used 09. No idea what kind of fluids they put into it. Can I flush, drop the pan, put in the proper ns2 fluid and not mess it up. I Know there is still fluid in other parts I can't get to. I don't want to mess up my transmission. But, I can't afford a shop to do it either. There's no telling if they'd even fully flushed it anyway. Would flushing and dropping the pan get enough of what's in there out? Or, is my best option paying insane prices for a pro to do it?