95 Grand Am tranny?? problems

I recently purchased a 95 Grand Am 3100 at a sale(whoops). Ran and looked good , but on the way home I almost had a heart attack. As I slow down to almost nothing and then accelerate it seems I put it in neutral for a bit and then hard slammed it to drive. Also, in park if you give it a little gas you can hear a thump thump thump... coming from what I think is the tranny area. I assume:screwy: they are related? Quite frankly, I can't afford to take it to a real shop and my so called neighbor mechanic(legal) says he'll swap with a used one if he can find one, no luck yet. I think it is a fixable, not replacement, item. What do my experts out there think? Thanks Mike

If its slamming, not good !!!
Could be the torque converter but I'd say its about had it.
If its not to far gone it can be rebuilt, though a used one is much cheaper.

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