Nissan Patrol 2000: Both the original and replacement engine failed

Many reports from the trade relate to the 3.0-litre diesel Patrol, and they don't make pleasant reading. It seems the motor suffers from head problems (head gasket leakage and cracking) which was fixed with a thicker head gasket that lowered the compression slightly. It also suffers from an oiling problem, which can become a worry when the Patrol is driven at highway speed in hot climates. Nissan increased the oil quantity to overcome this problem. I would suggest you keep a close watch on your engine, and perhaps ask Nissan for some sort of extended warranty coverage. Smaller used-car dealers are taking extended warranty on any 3.0-litre Nissan turbo diesel they sell to protect themselves against a problem later on, which should give you some idea of the how they view the vehicle.