nine outer CV joints are replaced for every inner CV joint
That does not mean the technician should overlook the
inner joints. They wear too. Every time the suspension
travels through jounces and rebound, the inner joint
must plunge in and out to accommodate the different arcs
between the drive shafts and suspension. Tripod inner
joints tend to develop unique wear patterns on each of
the three rollers and their respective tracks in the housing,
which can lead to noise and vibration problems.