speed is increased. A vibration that occurs within a
specific speed range is not usually caused by a pro-
peller shaft being unbalanced. Defective universal
joints, or an incorrect propeller shaft angle, are usu-
ally the cause of such a vibration.

DIFFERENTIAL & DRIVELINE

3 - 1

DRIVELINE VIBRATION

Drive Condition

Possible Cause

Correction

Propeller Shaft Noise

1) Undercoating or other foreign
material on shaft.

1) Clean exterior of shaft and wash
with solvent.

2) Loose U-joint clamp screws.

2) Install new clamps and screws
and tighten to proper torque.

3) Loose or bent U-joint yoke or
excessive runout.

3) Install new yoke.

4) Incorrect driveline angularity.

4) Measure and correct driveline
angles.

5) Rear spring center bolt not in
seat.

5) Loosen spring u-bolts and seat
center bolt.

6) Worn U-joint bearings.

6) Install new U-joint.

7) Propeller shaft damaged or out
of balance.

7) Installl new propeller shaft.

8) Broken rear spring.

8) Install new rear spring.

9) Excessive runout or unbalanced
condition.

9) Re-index propeller shaft, test,
and evaluate.

10) Excessive drive pinion gear
shaft runout.

10) Re-index propeller shaft and
evaluate.

11) Excessive axle yoke deflection.

11) Inspect and replace yoke if
necessary.

12) Excessive transfer case runout.

12) Inspect and repair as necessary.

Universal Joint Noise

1) Loose U-joint clamp screws.

1) Install new clamps and screws
and tighten to proper torque.

2) Lack of lubrication.

2) Replace U-joints as necessary.

3 - 2

PROPELLER SHAFT

PROPELLER SHAFT (Continued)

BALANCE

NOTE: Removing and re-indexing the propeller
shaft 180° relative to the yoke may eliminate some
vibrations.

If propeller shaft is suspected of being unbalanced,

it can be verified with the following procedure:

(1) Raise the vehicle.
(2) Clean all the foreign material from the propel-

ler shaft and the universal joints.

(3) Inspect the propeller shaft for missing balance

weights, broken welds, and bent areas. If the pro-
peller shaft is bent, it must be replaced.

(4) Inspect the universal joints to ensure that they

are not worn, are properly installed, and are cor-
rectly aligned with the shaft.

(5) Check the universal joint clamp screws torque.
(6) Remove the wheels and tires. Install the wheel

lug nuts to retain the brake drums or rotors.

(7) Mark and number the shaft six inches from the

yoke end at four positions 90° apart.

(8) Run and accelerate the vehicle until vibration

occurs. Note the intensity and speed the vibration
occurred. Stop the engine.

(9) Install a screw clamp at position 1 (Fig. 1).

(10) Start the engine and re-check for vibration. If

there is little or no change in vibration, move the
clamp to one of the other three positions. Repeat the
vibration test.

(11) If there is no difference in vibration at the

other positions, the source of the vibration may not
be propeller shaft.

(12) If the vibration decreased, install a second

clamp (Fig. 2)and repeat the test.

(13) If the additional clamp causes an additional

vibration, separate the clamps (1/4 inch above and
below the mark). Repeat the vibration test (Fig. 3).

(14) Increase distance between the clamp screws

and repeat the test until the amount of vibration is
at the lowest level. Bend the slack end of the clamps
so the screws will not loosen.

(15) If the vibration remains unacceptable, apply

the same steps to the front end of the propeller shaft.

(16) Install the wheel and tires. Lower the vehicle.

RUNOUT

(1) Remove dirt, rust, paint, and undercoating

from the propeller shaft surface where the dial indi-
cator will contact the shaft.

(2) The dial indicator must be installed perpendic-

ular to the shaft surface.

(3) Measure runout at the center and ends of the

shaft sufficiently far away from weld areas to ensure

Fig. 1 CLAMP SCREW AT POSITION 1

1 - CLAMP
2 - SCREWDRIVER

Fig. 2 TWO CLAMP SCREWS

Fig. 3 CLAMP SCREWS SEPARATED

1 - 1/2 INCH

PROPELLER SHAFT

3 - 3

PROPELLER SHAFT (Continued)

that the effects of the weld process will not enter into
the measurements.

(4) Refer to Runout Specifications chart.
(5) If the propeller shaft runout is out of specifica-

tion, remove the propeller shaft, index the shaft 180°,
and re-install the propeller shaft. Measure shaft
runout again.

(6) If the propeller shaft runout is now within

specifications, mark the shaft and yokes for proper
orientation.

(7) If the propeller shaft runout is not within spec-

ifications, verify that the runout of the transmission/
transfer case and axle are within specifications.
Correct as necessary and re-measure propeller shaft
runout.

(8) Replace the propeller shaft if the runout still

exceeds the limits.

RUNOUT SPECIFICATIONS

Front of Shaft

0.020 in. (0.50 mm)

Center of Shaft

0.025 in. (0.63 mm)

Rear of Shaft

0.020 in. (0.50 mm)

note:
Measure front/rear runout approximately 3 inches (76
mm) from the weld seam at each end of the shaft
tube for tube lengths over 30 inches. For tube lengths
under 30 inches, the maximum allowed runout is
0.020 in. (0.50 mm) for the full length of the tube.

STANDARD PROCEDURE

PROPELLER SHAFT ANGLE

(1) Place transmission in netural.
(2) Raise and support the vehicle at the axles as

level as possible.

(3) Remove any external bearing snap rings from

universal joint so protractor base sits flat.

(4) Rotate the shaft until transmission/transfer

case output yoke bearing is facing downward.

NOTE: Always make measurements from front to
rear and from the same side of the vehicle.

(5) Place Inclinometer 7663 (J-23498A) on yoke

bearing (A) parallel to the shaft (Fig. 4). Center bub-
ble in sight glass and record measurement.

NOTE: This measurement will give you the Output
Yoke Angle (A).

(6) Rotate propeller shaft 90 degrees and place

Inclinometer on yoke bearing parallel to the shaft
(Fig. 5). Center bubble in sight glass and record mea-
surement. This measurement can also be taken at
the rear end of the shaft.

NOTE: This measurement will give you the Propel-
ler Shaft Angle (C).

(7) Subtract smaller figure from larger (C minus

A) to obtain Transmission Output Operating Angle.

(8) Rotate propeller shaft 90 degrees and place

Inclinometer on pinion yoke bearing parallel to the
shaft (Fig. 6). Center bubble in sight glass and record
measurement.

Fig. 4 OUTPUT YOKE ANGLE (A)

1 - SLIP YOKE BEARING CAP
2 - INCLINOMETER

Fig. 5 PROPELLER SHAFT ANGLE (C)

1 - SHAFT YOKE BEARING CAP
2 - INCLINOMETER

3 - 4

PROPELLER SHAFT

PROPELLER SHAFT (Continued)

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