Splines And Bearing

WARNING: This page is about a different car, the 2011 Subaru Tribeca. However, it is still accessible from the selected car via links, so may be relevant.

Remove the center exhaust pipe.
Remove the rear exhaust pipe and muffler.
Remove the heat shield cover.
Turn the propeller shaft by hand to see if abnormal free play exists at splines. Also move yokes to see if abnormal free play exists at spiders and bearings.

Fig 1: Identifying Propeller Shaft
Courtesy of SUBARU OF AMERICA, INC.