also trannies are very delicate, once there is an issue such as non shifting (based on my experience with my tbird trans) once the componants are shot and dont work, they dont work, there coudl be some internal damage due to the either lack of fluid or viscosity of the fluid, if the fluid flows liek water, its not gonna flow though the trans right, also causing the car not to shift protecting the gears and neutraling out, im no expert, but in the past this has happened in my other cars, so thats what im going with at this point, as long as i can keep it thicker and it can flow with a thicker consistancy it shoudl in theory be ok.