On my subject car (110k miles)I have never changed the transmission fluid. Owners manual does not recommend changing except under severe service conditions. This car has led a pretty easy life service-wise. Half highway and half city miles with a gentle driver. Never had a transmission problem. The fluid seems clear but is developing a black tinge to it. Should I change this fluid out? I hesitate only because I've been told that changing the fluid with this many miles may create more problems than it prevents.