Sorry for the length in advanced....I want to give as much information as possible.

Sadly you will all hate me for this,

I was low on funds and life happened so my car sat for 3 years. Now I'm trying to resurrect it and having a few issues. One is the Dual electric fans don't work even with A/C but i think Ill just wire switches for that anyways. (Tested Relays and Fuses)

The main problem:

My tranny does not like shifting. I topped it off with fluid (cheap walmart ****) just to drive it from where it was to my house. I plan to rid that and put in new dexron and filter yadda yadda....

When casually driving, sometimes the car will not shift whatsoever...I can easily get it to shift at any moment by lifting off the throttle however. When Getting on it, it will scream and just not want to shift at all. I want to say that it is slipping too but i think it goes past the optimum rpm range for HP and im just not feeling the same acceleration higher in each gear. There is NO specific gear that this does this in. Sometimes it wont shift 1st to 2nd and sometimes it will etc....

I went through the TV cable adjustment process. (link is on here somewhere). Pulled the cable hard towards the firewall and actually pulled the rubber stopper through the bracket so I put it back through and snug with the bracket. The cable is tight WOT but is slightly kinked it seems. Im wondering if a new TV cable will be ideal. Another thing is the transmission crossmember underneath broke so I cannot beat on it too much. (tranny sits 1/4-1/2 inch lower on the right side). Could this effect the tranny not shifting?

Hopefully today I will get installing the new bracket and putting new fluid in there. I guess Im mainly praying the 700R4 isnt dead...

So high RPM shifts (when i lift the throttle it shifts) and sometimes feel like its slipping in random gears basically are my two problems. After adjusting the TV cable the problem has improved some....The car has a noticeable power increase and my issues are less severe. My buddy that drag races says it sounds like a fluid issue with sitting so long especially. I have also read about sticky governor and sticky valve spring. Based on my sporadic issues and how its random in all gears I hope someone can narrow this down a bit.

Thank you all for the help.

That trans needs work, open the wallet.

Could be a couple of things. If the trans is sitting lower it could be pulling on the tv cable causing it to stretch or bind. Fix the crossmember How is the fluid ie colour? Is it milky at all from water? The walmart fluid should be ok as long as it is dexron 3-4 approved.

I don't see how just letting it sit would affect the way the transmission shifts unless it was marginal when it parked.

I would repair/replace the x-member and re-adjust the TV cable and go from there. You might also have a governor that is stuck.

As for fluid, just use anything that is suitable for transmissions requiring Dexron III.

There is no such thing as an "approved" Dexron III. There were "licensed" (by GM) Dexron III's blended by companies such as Valvoline, Pennzoil, etc. But GM has pulled those licenses when Dexron VI was introduced.

There has never been a Dexron IV.

I like the governor stuck theory. Might try "miracle in a bottle" before yanking it.

Some Updates:

Had to re-tap a hole on the transmission bracket and fixed that up. The tranny was actually sitting closer to 4 inches lower on one side with that snapped bracket. So I decided to take it for a quick run. (Really quick BC I think some guy called the police on me ...again). I drove up and around the block and it shifted just. in OD 1st to second was around 3k and then I turned around and got on it. No slipping at all but the RPMs skyrocketted and the car was going like a bat out of hell but did not want to shift again. I had to let off the throttle...Again, this was a very short test drive. Im going to be working on getting the car legal so I can drive it around a bit more. My next step is finding where this governor is and if its not too hard to take out then ill try that. But due to the skyrocketting RPMs with the tranny sitting like that it may have stretched out the TV cable. I dont know, but Im steering further away from thinking it s a bad tranny which is good.

Thank you all for the advice! What do you guys think now?

Could be the governor sticking...

It will be on the driver side behind a round cover. You will have to remove the crossmember and let the tail drop in order to remove the governor.

The 700R4/4L60 is one of the more complex transmissions out there. If the governor is not the issue, you will need to have it rebuilt. On these older cars, personally I would try to rebuild the one in it. If you get a different trans then I would try to use the valvebody and governor from the original transmission. I know the IROC and the Z28 had some differences that were specific to those models.

The 3-4 clutch pack is a common set to burn up and fail. Keep this in mind.

Getting a good repair manual could help you to figure out what the problem is, or contacting a reputable builder like Dana at ProBuilt Automatics.

I was able to legalize the car and hit the street with it for a bit. It will downshift and take off in any gear with ease now. My speedo is stuck at 30 mph and my tach FLYS to 7000RPM early i the gear. I listen to the motor and let it go till i think its not going to shift and I let off the gas then it shifts. I will go through 60% of any gear with the tach at 7000 RPMs. It also slipped when I manually put it in 2nd and stomped on it a couple times. But the thing will downshift from D and go. Just not want to shift early enough still. Is there some possibility that the tach being off is what is causing my problems? I know the speedo is probably a separate issue. I bought a TV cable and I may just buy a new governor too so when I drop the trans I can do them both....But Im starting to think the tach could be messing with things....

no, teh tach issue is a resistor thing and has nothing to do with it. I've been driving around with my tach sitting on my desk in the garage for the last few days as mine was pegging as soon as you started the car. There is a good thread here on the forums about how to fix it. Takes about 5 minutes, a voltage meter, and a $.50 resistor from Radio Shack.

if youre broke as a convict ,you can sometimes get a few more miles out of it by using "seafoam" trans fix in a can. I have used it, and got 700 miles more than I would have otherwise.give it a try

the governor is under a round cover twards the back on the left side.and as for that .they have a plastic gear that sometimes wears out.(it causes the symptom you rescribe) now you have to get one with the same amount of teeth. BUT you will have a hard time getting the cover back on straight ,but it can be done. good luck

This is what I have been hearing a lot. I already ordered a TV cable so I may just replace that too when it comes. But the car is legal now and I have been regularly driving it. Regular road driving it has 0 issues whatsoever. Its only when you put the pedal down. So governor or TV cable are the most likely verdict and not something more severe. Guess ill start that process tomorrow! Thank you guys, ill keep y'all posted!

After going to and from work with it in the last week or so its performing much better. Maybe it needed to be run. But I can accelerate just fine from a dead stop. It only seems to slip a bit when it downshifts from say OD to 2nd but it soon catches and takes off. I still dont know if this is a TV cable or governor thing. I have a new cable and governor gear but need to get it to a lift. This is no job for being on my back for either one i dont think haha.