Seems to me that all D40's are affected with inadequate corrosion inhibitor applied to the chassis inside and out.
The thickness and strength of the chassis is an issue as is the chemistry of the steel used to make the chassis.
The Chinese will manufacture steel to any standard with a high degree of precision if you specify as such.
We have seen footwork better than Muhammad Ali by NIssan including blaming towbars, maintenance, overloading and sea exposure. Don't use inspection cameras when checking the safety of a chassis internals, what a joke. What will be next.
We still own a final generation of D40's on the conveyer belt going to destruction. NIssan could recall these, weld in the strengthening plates and rust proof the chassis parts.
They don't appear interested in this, they have done their sums and they understand people have short memories.
Overall it must be cheaper to let things roll. Are NIssan planning a buy back on the final batch of D40's when they all fail, who knows?
There have been no admissions of guilt from Nissan, I have heard of no Nissan engineers jumping off bridges. It's all a game.
They seem to know how to play the Government Departments that were established to protect the public from fraud and ensure products are safe.
If you want your D40 to last the distance then it seems it's up to you to do something about it, no matter where you live in the world.