that's going to depend entirely on the current condition of your trans. I'm gonna go ahead and assume you won't be doing any trans work on your own.
You could take it to aamco or something to have it checked out and get a quote but you're probably better off just ditching it and getting a new tranny
If you were looking for a quick/cheep fix sorry there aren't any u could try an additive & it might limp you through another 500 miles. Bottom like is that your transmission is going to have to come out....
I was in the same boat as you. Places want $1500 to $3000 just to rebuild. That tranny is a crapper. Your best bet is to find an importer and just replace it. I took my time and did it in a little over a day. If you do not want to do the labor be prepared to pay a shop $500-$1500 for the labor. If you have any mechanical abilities it is not that hard, just time consuming. Biggest pointers I can give for a do-it-yourselfer is to get a buddy who has a shop and use his lift. If thats not an option its going to suck but it can be done. Jack it up as high as you can and go to town. I digress...biggest pointers...
Disconnect everything including the front mount and crossmember, take all the 17s out of the tranny(tranny bolts) and leave it on the tranny mount. get a tranny jack and put it under the tranny. Put a 19 on the crank and spin it as you take off the 10mm bolts that hold on the tq converter. Once it is completely free minus the mount jack up the tranny and disconnect the bracket from the tranny. Blah, Im rambling and who knows if you are even going to do it. If you decide to do it hit me up with any questions, im sure there are write-ups on here as well. GL man
and yeah, for the short term drain and flush the tranny fluid. You can drive it for a couple more months if you dont beat on it. If money is tight now is a good time to start saving because you will need to replace this transmission. My buddy was the original owner on one years ago and it took a dump after only 38,000 miles.