when my 98 gets warm and is idling in any gearEXCEPTpark for neutral, i get a semi-loud cackling noise prob from the trans.
wtf is going on?! any ideas?!
thanks!

Does this noiserise and fall with RPM of the engine while in a drive gear? or just constant.

Probable cracked flex plate. Find a way to look at the bottom of the torque converter. Usually a cracked flex plate will have rust stains down from the cracked bolt hole holding it to the torque converter. Rather common failure.

Would appreciate a response to the noise. Did you find the cause?