Nissan Patrol 2001: Goodwill payment for turbo diesel repairs?

WE OWN a 2001 Nissan Patrol that has done 145,000km. Four weeks ago the engine went bang. Our mechanic advised us that a piston had a hole in it, which I am told is a known fault with the 3.0-litre turbodiesel because the pistons are not thick enough. Nissan claims to have resolved the problem since. As an "act of good will" Nissan has offered to pay for the engine rebuild kit, but we are still $4500 out of pocket for labour and associated parts. All this for something they accept blame for. This is far from "resolving the issue to the satisfaction of the owner", as per Jeff Fisher's letter to you. I keep getting told that we are out of warranty and Nissan won't do any more than they have offered. It's as if I should be thankful that I am getting anything from them.