P0780 Nissan -

Question

two workshops where they repair transmissions was told the transmission seems fine, but I can not say I do.
There is something that I can change it to see if it works better.
what about the speed sensors

Answer 1

The problem is inside the valve body of the transmission.

have you replaced the transmission fluid? I would start by replacing the fluid first USE NISSAN FLUID.

if the car is shifting hard or grinding gear the transmission will be bad and will need to be replaced.

You will need to flush the transmission lines before you can install a USED (recommended) or rebuilt transmission.