Transmission and Drivetrain: Description and Operation

Driveline System
The driveline transfers engine torque to the drive wheels. Power is transmitted through the transmission to the driveshaft and then to the axle, which is connected to the axle shafts.
For additional information on the axle shaft, refer to Drive Axles, Bearings and joints.
For additional information on the driveshaft, refer to Drive/Propeller Shaft, Bearings and Joints.
For additional information on the differential, refer to Drive Axles, Bearings and Joints.
The engine angle is built into the engine mounts. If the engine angle is out of specification, the engine mounts must be inspected for damage.

Driveline Vibration
Driveline vibration exhibits a higher frequency and lower amplitude than high-speed shake. Driveline vibration is directly related to the speed of the vehicle and is usually noticed at various speed ranges. Driveline vibration can be felt as a tremor in the floorpan or is heard as a rumble, hum, or boom. Driveline vibration can exist in all drive modes, but may exhibit different symptoms depending upon whether the vehicle is accelerating, decelerating, cruising, or coasting. Check the driveline angles if the vibration is particularly noticeable during acceleration or deceleration, especially at lower speeds.
In order to diagnose vibrations in the driveshaft, refer to PDU for analysis/rectification.

Driveline Angle
Driveline angularity is the angular relationship between the engine crankshaft, the driveshaft, and the rear differential pinion. Factors determining driveline angularity include ride height, rear springs and engine mounts.
An incorrect driveline (pinion) angle can often be detected by the driving condition in which the vibration occurs.
^ A vibration during coasting from 45 to 35 mph (72 to 56 km/h) is often caused by a high pinion angle.
^ A vibration during acceleration from 35 to 45 mph (56 to 72 km/h) may indicate a low pinion angle.
When these conditions exist, check the driveline angles.
If the tires and driveline angle are not the cause, carry out the NVH tests to determine whether the concern is caused by a condition in the driveline.

Vehicle Certification (VC) Label
For additional information on the vehicle certification (VC) label.





Able Identification Tag





Axle Identification Tag Denoting Interchangeability Affected Internally

CAUTION: The axle identification tag is the official identifier. Do not damage the tag. reinstall the tag after removing it.

The plant code denotes a particular differential design and specific ratio. In addition, the plant code will not change as long as that particular differential never undergoes an external design change. If, however, an internal design change takes place during the production life of the differential and that internal change affects parts interchangeability, a dash and numerical suffix is added to the plant code. This means that as an assembly both differentials are interchangeable; however, internally they are different. Therefore, each requires different internal parts at the time of repair.