As the title states, but my delema is that my car is still got the original fluid from when it come out of the factory. I am running a little low on it now and what should i do? Toyota doesn't stock the fluid that is currently in the car as they do a complete flush out and fill it with Dextron III. Should i leave it since there is sufficent amount, flush it out or try and top it up with the 'orginal' fluid if i can find it (or if someone can point me in the direction so I can top it up)...