The owner's manual appears to contain no recommended interval on when to change the auto tranny fluid on my 2010 Toyota Camry which I just bought at 86k and which has no record on any fluid changes. All the manual says to do is check the fluid every so often. I don't believe in lifetime fluids. What would be reasonable here? Am concerned that if I wait much longer, it might be too late and I might do harm. Have read a bunch of stories about trannies grenading when the fluid is changed after 100k. What do people think? Also, would prefer to use a synthetic fluid but my dealer put a 100k warranty on this car and I am concerned using non-Toyota fluid before 100k might void the warranty. Thanks as always for all thoughtful responses. After this initial change whenever, it might be, what interval afterward?