Fits years 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015
M226 Ring and Pinion Set w/ 24-spline Pinion.

Some Xterras were equipped with a 29-spline pinion from Nissan. In this case a 24-spline yoke is required. 
2004 - 2006 OE Yoke/Gearset is 29 spline. 
2006 - 2015 OE Yoke/Gearset is 24 Spline.