Close the engine fuel system, then remove the cable from the negative battery terminal. Place jackstands under your car, but lift only the front tires if you are doing maintenance work on a Xterra. The Xterra model puts its fuel filter right above the fuel tank on the crossmember frame. Wipe off dirt around the fuel entry and exit lines, then loosen the connecting clamps and untie the filter hoses from both ends. Have extra cleaning cloths or storage containers nearby in case gasoline leaks while you work. Loosen the bracket bolt, take out the fuel filter from its mount. You must put the filter in correctly, following the standard installation procedure. Additionally, switch out the old spring-type clamps with new screw-type ones.