This is an extremely important question, as it completely decides whether you should change your shocks or try to drive with them for a bit longer.  Here are some tell-tale signs that your shocks are not functioning as they’re meant to and it’s time to get some new ones:  1) Bouncy bumper This is one of the tell-tale signs that your shocks are not working. The bumper will usually bounce around and you’ll notice it, but if you want to be double sure, you can perform this quick test. Push down on each of the corners of your Nissan Xterra. If the vehicle continues to bounce even after you let go, your shocks need replacing. Good shocks will stop the bouncing almost immediately. 2) Unpleasant or rocky ride You’ll usually notice when the ride is getting too unpleasant. Roads you’ve driven along earlier that seemed smooth suddenly feel like gravel, and your body will be noticeably sore and exhausted even after a quick drive. This usually means that your ride is not very smooth and your shocks have rusted or stopped working. Replacing the shocks will restore the buttery-smooth ride you so loved at one point.  3) Oil leakages Another sign of malfunctioning shocks is oil leakages in your vehicle.