WARNING: This page is about a different car, the 2005 Nissan Xterra. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Removing & Installing Oil Cooler With Torque Specifications
Courtesy of NISSAN MOTOR CO., U.S.A.
WARNING:
Be careful not to get burn yourself, as engine oil and engine coolant are hot.