i hope someone can help me!!! I have a creaking noise in rear after driving..i can pull into my drive way (slight elevated) and it sounds almost like a body creak... noise is very loud..i also notice this when i accelarate or at slow speeds like going through parking lots... i have replaced rear diif mount..

noise is not present when body is cold... i hope some one can help..

i can also produce this noise by pressing down on rear bumper.. these ugly bumpers are good for something...

78 280z

Its probably just a bushing dude. Most likely the inner control arm bushings on the rear. They may be old and need replacing, or if they are new polyurethane bushings that aren't lubricated properly then the sqeaking is normal. Another possibility is the outer transverse link bushings which are a real pain to replace. A difference in temperture creating the sqeak would also point towards bushings. I'm pretty sure its not your rear diff mount because that would create a thunk not a creak, and the mustache bar bushings would thunk as well. I assume when you say "body creak" you mean that the chassis is flexing, but I don't believe that is the case either, as your S30 chassis is a true monocoque, that is one peice, not rubber isolated sub frames or anything silly like you find on modern cars. In other words, Don't worry about it, just whenever you get around to it replace the inner control arm bushings and see if it goes away.

would it be ok to lower the control just a bit and add some wheel bearing grease to see if this is the problem..thanks anyone:stupid:

If you go to all the trouble of lowering the control you could just replace the bushings. It's not very expesive and you will be doing all the work you would have to do anyway. Also, if you don't know what kind of bushings you have you don't know what kind of grease to use, wheel bearing grease, if it is petroleum based, will destroy a polyurethane bushing. You must use a synthetic grease with polyurethane. (White Lithium grease seems to work very well).