TCC Help ?

[eclivic]

Well the low down is this, I recently bought a 99 Sierra 1500 4x4 Z71. The brake lines were shot and the ABS module was getting moisture in it. I fixed those issues and put the truck on the road. The first thing I noticed was it would shift pretty hard from 1 to 2 but 2-3 3-4 were fine. So I added a BIG tranny cooler. Than the water pump started dripping, replaced the water pump. The truck has also always had a valve floating sound in it but Ive never really paid it any attention. One day I took a little drive about 45 miles, the valve sound was un godly loud, I then threw 2 codes, Cat and knock sensor. I never believe 02 codes on a chevy so I replaced my MAF. After replacing the MAF and clearing the code my shifts were smooth as butter from 1-4 and I had no more hesitation from the line at a stop sign. The o2 codes went away but the knock sensors codes came back a few times. (I did do a NGK plug change at time of MAF also.) well a few weeks have gone by and now I get NO codes but I still believe my knock sensors are the cause of the ping noise I still hear, because I do wash and clean my engine and I found out water gets into the sensors. I have them and im trying to get time to change them

Now for the new stuff. After the codes stop returning I now feel the TCC slip in and out when 40-45 ish - 70 mph under cruise speeds. shifting and driving are perfect until those speeds. Im now wondering with the MAF change, since it fixed my 1-2 harsh shift could of affected me TCC as well or even the knock sensors needing to be changed affect my TCC. 

I have read many many many forums and cant find anything the has my conditions, most either stay locked TCC or Never lock TCC. In my research I did read the TCC can be affected by missfires that arent felt all the way to the brake switch, in which I have install a remote start and it DOES connect to the switch.

So what would you guys think.

Tranny Cooler
MAF
NGK plugs Bad
Nock sensor
TCC Solenoid
Tranny filter/fluid change, (its not the pinkest)

I have to kids and a woman who dont make much at work so I am a broke MF. I hope you guys can help me figure this out and it not cost me 1300 rebuild.