Have a 1990 Chevy caprice.. 110,000 miles on the original engine, bought it two years ago.. no major issues...

The problem is this.. when driving.. i hear a rattle underneath the car, dont know if it is the transmission or what.. i think it is the tranny... but.. what do i know.. not much about this.

started when.. i was on the highway.. went from Overdrive to drive, (its an auto) and.. completely lost acceleration. I stepped on the gas, and nothing.. didnt go any further, i released, and stepped again.. and it went fine, and the rattling stopped.
i dont remember if the thing revved when i accelerated or not. This has happened twice, both times on the highway.

Now the rattle is pretty much constant, worse going over bumps.

I know it isnt the best car in the world.. but at the time it is all i have. and no means of getting another..

305 v8 1990... is the stock caprice.. not the classic.