I have a 96 Ram 1500, 46RE trans with a 318... I just got it running today, found that if I put in the Trans Relay it kills the engine... also while I do have it running I can put it in reverse and neutral and it works fine but the moment I put it in drive it dies instantly... by the way the relay is new and I have tried several new relays all doing the same thing...

 

Trans relay just sends power to the trans. (oddly enough..... ) check the wire from the relay socket, to the trans, see if it is grounding out somewhere. (Unplug it at the trans as well. 8 pin connector, about halfway back on the drivers side of the trans.)