transmission jumps rpms in overdrive
 

it only happens when going up a hill at like 40 mph or when going around a sharp corner like an exit ramp on the interstate. if I engage the brake it will instantly stop and down shift and its fine. it wont do it when its running over 50+ mph. only does it when your slowly going into overdrive. ive read it could be the torque convertor and that's why it goes away when very lightly applying the break and then I read I could just need a shift kit installed and it would go away. anyone else ever have this issue and a fix for it? BTW: 1999 blazer ls 2 door 4wd, 4L60E.
THANKS EVERYONE! :icon_beerchug:

It's normal for your RPMs to jump 200-300 when the torque converter disengages. This happens when you step on the brake, or when the load on the engine increases, or you go slower than the PCM allows TCC operation.

Ok well with that being said, when I first start it after it's been sitting for a couple hours or so, if I try to jump in and go when I accelerate quick it bogs down and slowly builds up but right when it shifts it bogs again. It doesn't this through all the gears at the beginning of each one but after it shifts through them all once like this it is fine, good to go. Almost like fluid isn't being pushed around like it should?
Also, thanks for the response!