Copyright Meritor, Inc., 2021
MM-96147 / Revised 03-21
Page 72
(16579)
Printed in USA
13 Troubleshooting
5. Use a dial indicator to examine the slip yoke spline for
excessive radial movement. Radial movement between the
slip yoke and the tube shaft must not exceed 0.017-inch
(0.432 mm).
• If the radial movement exceeds 0.017-inch
(0.432 mm):
Replace the slip yoke and the tube shaft.
6. Inspect the driveline for damage or bent tubing.
• If the driveline is damaged or bent:
Repair the driveline
at a reputable driveline repair facility.
7. If necessary, carefully remove mud or road debris from the
driveline.
8. Inspect the slip yoke spline seal for grease leakage or seal
damage.
9. Inspect for missing balance weights, damaged tubing or a
missing welch plug at the slip yoke.
For second order drivetrain vibration, refer to “Measure Driveline
Angles” in Section 14.
Table H: Vibration
Condition Cause
Correction
Driveline vibration
Driveline phasing incorrect
Correct the phasing by aligning the yokes on both ends of the
driveline.
Missing balance weights or foreign
material on driveline tubing
Have the driveline balanced.
Transmission or axle end yokes loose Inspect for radial looseness. Tighten the nut or replace the end
yoke.
Excessive end play in universal joints
Replace the universal joints.
Excessive hinging in slip section
Replace worn components.
Welch plug loose or missing in slip
yoke
Replace the welch plug or slip yoke.
Worn center bearing
Replace the center bearing.
Chassis ride height too low or too
high
Readjust the ride height.
Torsional accelerations in driveline
Measure the transmission, driveline and axle planes. Record the
readings and run the Driveline Analysis Program.
If the angles are found to be out of specifi cations, adjust or replace
components as directed.
Loose, missing or damaged driveline
fasteners or parts
Tighten loose fasteners, and replace damaged and missing parts.
Low gear shudder at full drive
or full coast under light load
conditions
Incorrect phasing
Reassemble with correct phasing.
Driveline weight incompatible with
engine-transmission mounting
Install a two-piece driveline with a shaft support bearing.
Driveline too long for speed
Install a two-piece driveline with a shaft support bearing.
Loose outside diameter fi t on slip
yoke spline
Change the slip yoke and spline plug.
Universal joint loose
Inspect the universal joint for looseness; tighten to specifi cation.
Replace if necessary.
Driveline out of balance or bent
Rebalance or replace.
Worn universal joint
Replace the universal joint.
Torsional or inertial excitation
Reduce the universal joint continuous running angle by adding
shims to driveline components.