Hey guys need some help. Ive got an 03 T4R sport 4.0 v6 with 100k miles, under normal driving conditions it says dont change TRANS FLUID, to my knowledge it hasn't, Ive got different answers from Toyota mechanics, some say change it, some say don't, b/c it could cause dammage. It still shifts smooth and runs like new and i would like it to continue.WHAT SHOULD I DO.