3.0 litre turbo failure-update

Several pages back a post reported a 3.0litre Turbo failure and their dealings with Nissan warranty.
My engine failed 13 months ago and was replaced under the out of warranty program.(118,000km)
The motor included a new Turbo.
Recently the turbo developed a Buzzing noise under acceleration and oil is leaking into the intercooler from the Turbo seals.
Returning to Nissan the claim was initially knocked back as the Warranty had expired(12x20,000km).
A call to Nissan public relations, and quoting an assurance that I would be "considered" if any problems occured within a reasonable time with the new engine,the decision was reversed and a new unit supplied with labour at cost.
I consider that a 20,000 or 12 month warranty on a new engine to be very poor,but it is apparent that Nissan is prepared to stand by there product beyond this if approached correctly.
What I have done with all dealings with Nissan is to write to the customer relations dept listing my concerns,I did this after the new motor was installed and it was in the response to this letter that the "consideration" was offered that has seen them cover the turbo on this occasion.
I personally have found them fair and reasonable with my dealings with them,this does not however excuse them for the ongoing problems that the early 3.0 litres suffer from.
During my discussions the 3.0 litre engine failures were explained as lack of oil getting up to the piston areas on high speed operation,this rectified by increasing sump levels and modifying oil jets,why the Turbo failed after 5000 km oil changes,the best oils, regular idling down I cannot say,I just hope it was a Monday build and the rest are okay.
Regards