Wow, you would not think you could notice .3 mph. How do the linkages work? Do they feel stiff or like something is not moving like it should? I would also check and see how the hydro fluid looks. You never know if it has been changed or if the filter has been changed. I could be speaking out of turn here because something tells me that the x300 trans is not serviceable?
Someone with more knowledge will speak up soon.
Someone with more knowledge will speak up soon.