4 spd auto trans shift pattern/kickdown rpm adjustment ?

Is there any way that the auto trans shifting behavior can be adjusted ?
I think it is a A304F ? , base 4wd , 4cyl ( shows 3 gears and OD on the shifter)
I believe it is "kicking down" way to early, so it cant pull a top gear on a grade, instead of getting throttle for more power it kicks down to 2nd when any throttle is applied
I got it used about 10k miles ago and it was always this way, at first I thought it was normal because the 4 cyl has not much power so it needs to get a lower gear but then lately I noticed that it tries to hold the gear and rpm keeps falling if the throttle is left at the same position, but as soon as I try to give it more throttle to hold the gear, it starts to increase power for a second then kicks down to 2nd way before it needs to, then keeps shifting back up to 3rd , so I usually just shift it manually to 2nd so it stops "hunting" for a gear up and down.
I don't see how it could ever hold 3rd gear on a grade if it won't let me give it any throttle at all when it is in 3rd manual (or OD) on a normal state highway grade
.......Just like the old school hydro drive autos when the kickdown vacuum pod on the carb needed adjustment
Very annoying having to pull every steep grade in 2nd (any hill that needs more than 1/4 throttle in 3rd ), not very noticeable on flatland or slight grades other than feeling a little sluggish because of less than optimum shift points, but think maybe that is normal for a 4cyl.
I checked the MAF sensor operation by pulling a grade at full throttle and reading live data on a generic code scanner for "% CALC LOAD" and it shows over 95% CALC LOAD, so MAF should be working fine, but I have not checked the TPS yet, I was thinking maybe one of those is sending a bad signal for when to downshift