Mitsubishi Repair: 1994 auto tranny 3000gt problem, mitsubishi 3000gt, drive gears

Question
Thanks so much. We replaced the fluids and it stopped the transmission from smoking out the exhaust. After we replaced the filter and everything it stopped jumping into gear. I do believe this car may have been towed in park. Not sure if that has anything to do with it being this silly. I talked to a tranny specialist he wants to replace the whole tranny. I am like mister it half works cant you rebuild it or fix the issue. They want to just replace it for 2000. Lordy. We have been looking for a Haynes manual havent had luck. But thanks for the tips.
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-----Question-----
I just bought a 1994 Mitsubishi 3000GT,3.0 DOHC,non-turbo, automatic and this car didnt start when I first bought it. I replaced sparkplugs fluids and filters so on. Get all the TLC done and it starts up like nobodys business. Excited I back it down my driveway and get out onto the busy main street and put it into gear. The car jumps into gear I press the gas pedal and BAM nothing. I had to do reverse donuts to get my car back into the driveway what a site. So my husband and I mess with it (he is a mechanic only specializes in large machinery engines) and we can not figure out why it is doing this. After fiddling with it now it wont jump into the drive gears. But if you get it at a certain RPM around 3000 it will  roll forward but that is it. HELP! cause the tranny places want to charge 2500 dollars. Thanks
-----Answer-----
Briana: You need to start the car, let it warm up to temp then check the transaxle fluid, see if it is brown(a sign that it is old and should be changed) or red as it should be. Smell it, does it smell burnt(hard use)? Could be someone pulled your car in park and so took care of your transaxle. But there are some things you can do, you should replace the fluid and filter to see if that does anything for it. Check the shift lever linkage and the manual lever on the transaxle. You need to get a repair manual that covers your car and it will give you other ideas to try. I like Haynes as they are easy to understand, walk you through things and have pictures. With your husband knowing how to work on engines they are about the same for the most part. You get that book and together the two of you can go down the list in the book. It could be something easy or it could be something hard. In that the car will have to hit a shop someplace. But with the manual you would be able to know what and how it will take to get the car running again. So should help with the costs, some shops will charge you more than they should. Hope this helps and good luck!

Answer
I would think you could have it rebuilt for a lot less than $2000.00. I was think about around $600.00 to $800.00. I mean you could maybe go to a junk yard and get one there from a junked car; put that in, for less than $2000.00. That $2000.00 is more than the car is worth. Or maybe you should check around, you might find someplace cheaper. You have to watch those shops, they know the car is down and you want to get it running. They think they have you over a barrel or something. I shall look around to see if I can find that manual. But mean while have you a library close by? They have books, you might not be able to check it out but you could have copies made. I do hope this helps you and good luck!