However, certain conditions must be met before cancellation will take place: The angle
between the transmission output shaft and the propeller shaft must be the same as the
angle between the propeller shaft and the axle assembly input shaft. In addition, the two
yokes on the propeller shaft must be aligned with each other. With this arrangement,
one joint turns at its greatest speed while the second joint turns at its slowest speed. This
results in an almost constant output speed to the driving wheels. (The speed of the
propeller shaft between the two joints, however, still fluctuates.)
In a universal joint, bearings are included at the four points where the journal is attached
to the yokes. There are several different kinds of journal-type universal joints. The main
difference among them is the way the bearings are attached to the yokes.
FIGURE 5. ONE TYPE OF JOURNAL UNIVERSAL JOINT.
Consider the universal joint shown in this figure. The journal is placed in the slip yoke, and the bearing
assemblies are inserted from the outside and secured by spring retainers (also called snap rings) inside
the yoke. The bearings on the other ends of the journal are secured to the flange yoke by clamps and