When my Nissan Navara D40 had its 80,000 km service the dealer found the thread of the sump plug came out with the plug. The bottom half of the sump had to be replaced at a cost of $500. We have extended warranty, but it is not covered. We're told it is a common problem with the Nissan and that it could happen again. Have you heard or been told about this problem before?
It is an often reported problem with the Navara. It's too late to fix your car, but it's important that the sump plug gasket is replaced every time the oil is changed, and that the plug is not cross-threaded when installed, which could have happened at a previous service on your car causing it to jam in the thread, and that it is not over-tightened.