Help. Cannot find noise.

[caltanian]

My 70 240z has a hell of a noise. From a stand still, it ratchets, about 4-5 times. Once on throttle, no more noise, but it occurs if i let off throttle, and then back on.

Its not there at any other time, and i cannot seem to find what it could be. Anybody had anything similar, or ideas on where to look?

Thanks.

[SteveJ]

Get under your car and look at the U-joints in the drivetrain. Inspect for wear. Make sure the differential is not able to move around.

[Mark Maras]

The ratcheting, You can hear it, can you feel it as well? What part of the car is it coming from? Can you feel it in the shifter, the body, the seat or the pedals? Also, have you noticed any changes in the car previous to this noise? Any info you can share, no matter how trivial, will be a big help.

[caltanian]

The ratcheting, You can hear it, can you feel it as well? What part of the car is it coming from? Can you feel it in the shifter, the body, the seat or the pedals? Also, have you noticed any changes in the car previous to this noise? Any info you can share, no matter how trivial, will be a big help.

I have replaced the ujoints in the driveshaft, and will be replacing the ones in the half shafts soon. Its more a noise, kinda able to feel it. seem to be coming from the rear suspension. The noise has always been there, as im just partly into a restoration of the car. replaced the springs as well, but the noise was there before and after.

[caltanian]

I can feel the nose when i touch the suspension upright in the rear. I plan to tear it all apart soon, but would love to knwo if anyone has any experience in this. Thank you.

[Sean240Z]

I had a thunking noise in my 240Z at one point, whenever I got on or off the throttle (though I would not describe it a s a ratcheting sound). Turns out the rubber on the diff mount was completely torn free from the metal portion of the mount. Replacing the mount solved my problem. Not sure if that is the problem you have though.