Dies when put in gear
 

I now have a new problem with my truck. Randomly at a stop light my truck died. I put it in park and it started fine but as soon as I put it in gear (R,1,2,D, and OD) it stalls out. Sounds like something. With the torque converter. Like the lockup clutch is stuck on. I was reading a little bit about similar problems and some people say it is the Trans solinoid? I have an 87 ranger and it says it only has one. Other people said that there may be something stuck in the valve body of the Trans. Preventing a valve from opening or closing. I would like to hear what you all have to say. Thanks a lot.!