Originally Posted by Quicksilvers

If you can’t or don’t have the means of doing the rear differential bushing install yourself take your Z to a shop or Nissan dealership service department you trust to do the install for you. This is an ideal job for a transmission/driveline shop. Depends on if you are on stock suspension or not will also depend on what noises you will hear from your suspension as well. Also consider the streets/highways you are driving on as well. Most of all brand polyurethane differential bushings for our Z’s have the same characteristics and noise level as the Genuine Nissan OEM rubber bushings don’t be afraid to install them and polyurethane bushings are also more durable than rubber bushings in turn they will last a lot longer. Performance wise it will improve with the polyurethane differential bushings but you will still have some play in the rear. I have been running solid differential bushings on every Z I have had only really notested noise with the solid differential bushings the polyurethane differential bushings are overall quiet.