Savana 1/2 Ton Van V8-5.3L VIN T (2003)
Drive/Propeller Shaft: Description and Operation
Propeller Shaft Description and Operation
The Propeller Shaft is a tube with universal joints at both ends which do not require periodic maintenance, that transmit power from the transfer case
or transmission output shaft to the differential.
Front Propeller Shaft Description
The front propeller shaft transmits rotating force from the transfer case to the front differential when the transfer case is engaged. The front propeller
shaft connects to the transfer case using a splined slip joint.
One Piece Propeller Shaft Description
An one piece propeller shaft uses a splined slip joint to connect the driveline to the transmission or transfer case.
Two Piece Propeller Shaft Description
There are three universal joints used on the two piece propeller shaft, A center bearing assembly is used to support the propeller shaft connection
point, and help isolate the vehicle from vibration.
Propeller Shaft Phasing Description
The driveline components in this vehicle have been system balanced at the factory. System balance provides for a smoother running driveline. These
components include the propeller shafts, drive axles, pinion shafts and output shafts. Affixed to the rear axle is a system balanced driveline notice
indicating that the driveline components have been factory tested. The propeller shaft is designed and built with the yoke lugs (ears) in line with each
other. This produces the smoothest running shaft possible. A propeller shaft designed with built in yoke lugs in line is known as in-phase. An out of
phase propeller shaft often causes vibration. The propeller shaft generates vibration from speeding up and slowing down each time the universal joint
goes around. The vibration is the same as a person snapping a rope and watching the wave reaction flow to the end. An in phase propeller shaft is
similar to 2 persons snapping a rope at the same time and watching the waves meet and cancel each other out. A total cancellation of vibration
produces a smooth flow of power in the driveline. All splined shaft slip yokes are keyed in order to ensure proper phasing.
Universal Joint Description
The universal joint is connected to the propeller shaft. The universal consist of 4 caps with needle bearings and grease seals mounted on the trunnions
of a cross or spider. These bearings and caps are greased at the factory and no periodic maintenance is required. There are 2 universal joints used in an
one piece propeller shaft and 3 used in two piece propeller shaft. The bearings and caps are pressed into the yokes and held in place with snap rings,
except for 2 bearings on some models witch are strapped onto the pinion flange of the differential. Universal joints are designed to handle the effects
of various loads and rear axle windup conditions during acceleration and braking. The universal joint operates efficiently and safely within the
designed angle variations. When the design angles are exceeded, the operational life of the joint decreases.
Center Bearing Description
Center bearings support the driveline when using 2 or more propeller shafts. The center bearing is a ball bearing mounted in a rubber cushion that
attaches to a frame crossmember. The manufacturer prelubricates and seals the bearing. The cushion allows vertical motion at the driveline and helps
isolate the vehicle from vibration.
