On another Pathfinder forum, there was a discussion about this, and here is what was said about the CVT in Nissan's models:
The prior CVTs were belt driven, and they were known to be highly problematic in their earlier incarnations in both the Altima and the Murano. In fact, Nissan had to extend the powertrain warranty to 10 years / 100K to further instill consumer confidence. They were doing this all the way up into the 2010 model year. At some point, they discontinued the practice.
For the (R52) Pathfinder, Nissan redesigned the CVT to use a chain. The intent was to increase towing capacity to make it competitive in the class. The (Infiniti) JX35, though a platform-mate, continued to use the earlier belt-driven CVT up until 2014 when the name was changed to QX60. As soon as Nissan made that change, the QX60 started exhibiting similar symptoms. (the shudder)