Need auto tranny help
 

I just bought a 98 Toyota 4 Runner. I bought it knowing it has a tranny problem. I bought it for $3500 and figure I would have a nice little truck once I fix the tranny.

Problem is, the tranny will not go in reverse. It also never disengages even while in park. The engine does not rev freely while in Park or Neutral. When I put it in reverse, it engages but does not move. When I put it in Neutral, the car goes forward but only stays in first. When I put it in D, the car drives forward fine and shifts through all the gears.

so first, what is the model code for my tranny? I know it's made by Aisin.
It's a 98 4 cylinder 2wd.

second, is there anything I could look for if I pull the valve body? I already pulled the pan and replaced the filter and checked the linkage.

third, anyone have any luck with these JDM trannys from ebay? I found one in a local yard for around $400 and would like to avoid getting a rebuild.

Thanks a bunch