Do I need to tune my old stall?

[BowlingSS]

I have not had to tune my stall/trany for four plus years. I have noticed that my RPM's seems to be higher in part throttle and up. At 70 the rpm is still 2K but lower speeds seem higher. Do stalls slip more after a few years? I have EFILive COS5 and the stall is a TCI SSF 3500. I change my trany fluid often and I have a deeper trans pain and a cooler.
What does everyone think?
What should I log to check this?

Thanks.
:cheers:
Bill