95 crown vic shifting

Flushed my system and added some lucas trans fix and it worked great for a while. But lately it sort of jerks when I'm on a hill or hitting around 40's.

not sure whats going on I was having a vibration problem but hat went away with the trans flush but now it just sort of jerks. Is this a sign hat the trans is going out? and what kind of trouble am i looking at when I get this fixed

How long since the plugs and wires have been changed? Sounds like you have an engine miss that is more noticeable under load. If plugs and wires are OK, the problem may be in the torque converter. I would go to the plugs first.

Plugs and wires, I seem to remember changing the plugs but honestly not sure. And if I'm not sure I'm gonna redo it to be sure.
I was having a vibration problem a while ago and we flushed the system and it stopped. We said it could be the converter then.

So lets play devils advocate if it is the converter, what kind of repair costs am i looking at?

The OE converter is about 300$ And it pays around 3.5 hours to replace. So price the converter and figure how much per hour you are being charged and you can come close. If you do it yourself, it is dirty, cramped and heavy, but labor will be cheap.