I am helping a good friend of mine with his 84 300D. I'll give you the brief history of what has recently been done. The car had lost all forward motion so we went ahead and replaced the b2 piston in the trans. Upon completing this, the car nows will move again! It runs and the tranny shifts, but first revs a little too high before shifting, and second is almost non existent. When it shifts from 1st to 2nd... it kinds lurches into gear if you know what I mean. Once the thing gets going above 35 or so... it runs amazing. The biggest issue it has is with hills. Unless you hit a hill doing 40 miles an hour, it will creep up hills at 20 miles per hour with the foot to the floor. It will not downshift when going up the hill and you get stuck in a higher gear so 20 is the top speed. Have already changed out fuel filter... not sure where to go from here. Could Vacuum have something to do with this? Injectors maybe? Something else in the trans? If this was your car where would you start? He's not willing to dump aton of money into this thing unless it will fix the problem... even then... not a whole lot. Any help would be much appreciated. It would be great if it could keep going. 250,000 +!!! Thanks for taking the time to read this!