Mitsubishi Repair: torque converter, torque converter, chrysler dealer

Question
I have a 90 eclipse 1.8 auto.  I was driving on the interstate when all of a sudden it shifted down a gear and then shifted back up.  It did this 2-3 times and then stayed in 2nd until you would shut the car off and wait a while.  It continued this problem, so I took it to the chrysler dealer, no mitsu dealer close, and they have had it about a month and a half.  They said that it is not electrical and have narrowed it down to the torque converter.  He said it shuttered.  The quote was about $1600 for new converter and install.  He said there is no reman converter available.  Does this sound like a converter problem?  Should I try to change the fluid and filter first?  If so is it necessary to use mitsu fluid?  What about an additive?  Any info helps.  Thanks

Answer
Landon,
A new torque converter will cost around $800-$900, and most dealerships charge about $85-$100 per hour, so their quote for a new torque converter install sounds about right.  But that's not to say that you actually need a new torque converter.  If you have any doubt, I would find a local transmission shop in your area to inspect your transmission and see if they diagnose the same problem as the dealership.  

But trying to change the fluid and filter as a first step is a good idea.  Your owners manual should tell you the proper fluid to use, but I don't think you need to get it from the dealership.  Though I would recommend you get the tranny filter from the dealership to be sure its a direct fit.  There are no additives that you'll need.
Good luck!