Spicer Drive Axles Service Manual G & M - Manual (Page 7)

This Spicer axle assembly consist of a full float, cold formed and welded, banjo-type housing member to which the
differential carrier assembly is bolted. The banjo housing is the vehicle load carrying member, and the differential
carrier assembly is the torque transmitting portion of the axle. It consist of a primary hypoid gear set for high range
operation, and a secondary planetary type spur gear set, which is combined with the primary gear set, for low range
operation. Range changes are easily made by means of a hand control button mounted on the gear shift lever
(See
Two-Speed Operating Instructions, Pg. 25) The control button causes the planetary sun gear to act as a sliding
clutch member, and moves it in and out of engagement with two clutching plates to complete range changes.
HIGH RANGE
In high range, the sun gear locks the planet gears with
the planet plate and the ring gear. The unit then
functions as a single reduction axle. Power flows in the
pinion to the ring gear through the differential case to
the differential cross shaft. The cross shaft transfers it
through the differential pinion mates to the left and
right differential side gears, and finally to the axle shafts. LOW RANGE
In low range, engine power is transmitted to the hypoid
ring gear as before. It then flows to the ring gear
internal spur teeth, which transfers it to the planet gears
that are attached to the differential case. Because the
sun gear is clutched to a stationary retainer plate, it
cannot rotate and acts as a reaction member for the
planet gears. This causes the planet gears to rotate
around the sun gear, driving the differential case at a
speed slower that the ring gear, creating the additional
low range reduction ratio and further multiplying engine
torque. From this point, power flows in the same
sequence as when the axle is in high range.
TWO SPEED AXLE FEATURES
5
POWER FLOW DIAGRAMS