Mikey I understand your principle, and I have applied it to a failure on my 1990 Montero. Designed for 225 tires, and having 33s then 35s for the last 100,000 miles. Both rear axles incurred a slight twist in the splines causing rear axle leaks. This is a well documented fatigue failure on 4x4s with large tires. Luckilly it took a long time to happen.

But fatigue failure on spider gears? And after only 6 trips off-road, 5 of which short, casual trips? And only 2 trips with a 1" larger tire?

I submit they CANNOT prove that the larger tire or lift alone could have caused the failure. AND...
They have to argue why...

1. There are thousands of failures of the exact same nature, regardless of use off-road or tire size.
2. Why they switched to a 4 spider diff sometime in 06.
3. Prove that the 2 spider gears, small cross pin and thin locker gear are not under engineered.
4. Why they promoted and helped design the lift, and display it on no less then 2 company vehicles and allow dealers to install them.
5. Why there diffs are some of the only ones ever designed with such a small factor that they cannot handle stock tires or 1" larger tires, including the brutally weak D35. And why are they 40% smaller/ weaker then prior Xterras with smaller tires, less HP and Torque and less weight? And why can everyone run 33s on those diffs without explosions?