I'm getting a loud "clunk" coming from the rear end when I take off from a standing stop with anything more thand grandpa type acceleration.

It's almost a bang sound coming from the rear...I'll also hear a quieter bang as it feels like it's settling back.

I'm not seeing it at any other time other than from the standing start with moderate acceleration.

Does this sound like a trans or torque arm mount that's broken??

It's almost like tranny doesn't react immediately and by the time it catches up it really stresses the drive train. (I'm hoping it's not anything inside the tranny...).

This is a 91 V6 with automatic...

 

that sounds like the typical tranny mount problem. They're easy to replace, so do that first. Then if it still happens, jack up the back of the car, put it in park, and see how much you can turn your rear wheels, and if it still clunks.

 

I have the same problem. Did you find out what yours was?