Recently, I'm hearing a creaking sound when I let off the gas pedal on my '74 260Z. Not being real savvy about the drivetrain in general, it sounds like it is either coming from the drivetrain or maybe from the rear struts; it's virtually impossible to tell where it's coming from.

It starts as a very sharp metallic creak when the Z is cold, but as I drive it, the creaking gets less noticeable. Any ideas?

http://www.classiczcars.com/forums/showthread.php?s=&threadid=10045

This link will take you to the thread when i had a something like you describe. In the end I loosened the front diffy mount and sparyed WD40 all over and the creak went away. But as you will see, most of the time the problem is with worn mounts and/or bushings in the moustache bar.

Old rubber will Creak until it warms up, Lot less when you use polyurathane bushings.

Just my 2cents

Dave