I got my tranny replaced about 3 or 4 months ago with a tranny that has about 60k miles on it. it seemed to be working fine for a while, but a few days ago, my alternator died on me. i know this has nothing to do with the tranny but ever since i got it replaced, the tranny has been shifting differently. i don't think it's really "slipping," but it seems to be shifting opposite what i would logically think it should do. like when i'm cruising and give it some more gas, it will sometimes upshift and go into the low o/d gear rather than downshift to give more accelerating power.
it also downshifts at very weird times for no apparent reason. like when i let off the gas some it will downshift very quickly and then upshift again. it seems like it gets confused or something very easily. it's not that big of a deal but it didn't used to act like this so i know somethings not right with it. any suggestions? of what it could be? could it be the tcu? also, would a tranny do that if it was slightly over or under-filled with fluid? (there is a very very small leak in the tranny fluid and once every 2 or 3 months i have to put a quart in but it's hard for me to get it exact)

 

Did you get a warranty?
If not this could be a real pain in the butt.
From what you describe the first thing I would do is carefully examine the harness going to the tranny and make sure it isn't cut or damaged.
Then check the tranny ecu and make sure it is operating properly. The easiest way is finding a used one that you know works and swap it out. After that I would suspect the valve body.
I'm not sure if buying another used one is cheaper than going through all this trouble. What did you pay for the tranny and where did you get it?

I don't think the fluid problem you describe has any bearing on the problem.

 

I got the tranny about 5 months ago and it had a 3 month warranty on it

if there was something wrong with the computer wouldn't it make the O/D light blink in a pattern when i start the car?

have you ever heard of this problem happening? it's very weird. it shifts backwards lol. wtf?

 

Well when your cruising and you accelerate more heavily it will go into your o/d "passing" gear where the rpms will shoot up and the car will take charge. I dont think it should downshift when you step on it when cruising. If your going up a hill and you step on it, then it will downshift.

 

downshifting is when the "rpm's shoot up and the car takes charge." if you're cruising, whether it's uphill or downhill, and hite the gas it should downshift right away. my problem is that it tends to upshift first and then realize its mistake and then downshift to correct. it does twice the amount of shifting necessary...