I have the same problem on my 2013 Leaf that I purchased 4 weeks ago. The passenger side of the rear bumper had a bigger gap between it an the metal rear quarter panel of the car, also it was loose so that when you pushed on it, it moved. It had also scraped paint off on the lights on both sides of the car where it had been too tight on the drivers side, and moving about on the passengers side.
I took the car back to the dealer, who then sent it to their body shop, who have been working on it for a week. The tried refitting the bumper, which failed. The then aquired and painted a new bumper, which also did not fit. They also tried the bumper of another leaf they had in the shop. Then they took some measurements of the of some welded metal panels on the passenger side rear of the car and determined that parts were welded 5mm out of allignment.
They then sent someone from teh body shop over to the dealer and discovered the same missalignment on EVERY SINGLE NEW LEAF on the lot.
This is obviously a manufacturing defect. As one guy at my work put it, "when they installed the welding robot, someone must have tripped over the extension cord and knocked it out of allignment."
The body shop is doing their best to refit the bumper so that it doest rub or move, but they are unable to fix the problem. I guess this could potentially become a BIG headache for Nissan. The warentee states that it covers any manufacturing defects, and this apears to be that. 5 mm is a BIG missalignment in my book.
