This is a good question. My mechanic indicated that the previous mechanic who worked on the transmission may have used red fluid. Said the fluid which came out was brown. Transmission shifted great, but I noticed the occasional hard shift from 2-3 when cold. Doing a drain and fill actually helped alleviate most of it.
I'm at 337k km now and trans feels strong. The pan has been dropped 4x, and 2x drain/fills.
I've also experienced this very strange surge only on upshifts, only from gears 2-6. Resetting the transmission resolved this and has not come back.
However, I notice that if I try to reset the transmission (adapt reset procedure) and am not successful, the upshift surge from 2-6 returns, forcing me to keep trying until it is successful. Otherwise, transmission shifts fantastic even when I compared to a CX-5 with only 36k km on it.
@sinistriel@ please give me your thoughts.