k1500 rpm go up when driving

[garftree]

ok i cant figure this one out, i have a 1995 k1500 z71 with a 350 and 4l60e trans with 172k on it. now i just made a trip to the catskill mountains (about 1800 miles with loads of hills) and when i got back it started freaking out when driving i could be going at any speed the rpms go up i thought trans but the rpms only go up like 500rpm max 800 as if it is slipping, well i am still moving forward the entire time so i dont thikn my trans is slipping, even when i am in cruise control it does it, its acting like its still in the mountains going up hills, i reset the computer still doing it. i am at loss here. no codes no lights on dash nothing. any help ideas would b great

[2000CAYukon]

Does this happen at constant throttle position only? Might be TCC lockup issues caused by a bad TCC Regulator valve in the valve body.

//2000CAYukon

[garftree]

it happeneds when ever touching the throttle, happens in cruse control, and acceleration. what i thought it might be is the tcc is unlocking and locking when it shouldnt, i am not sure the ways of trans inside and out, just basics. i was told to change the fluid, i also heard if it has more 60k miles on it dont change the fluid, well its got 173k on it now.