General Procedures - Driveshaft Runout and Balance

Special Service Tools / General Equipment

100-002 (TOOL-4201-C) Dial Indicator Holding Fixture

Inspection

1. 1
   • Perform a visual inspection of the vehicle. Drive the vehicle and verify the condition by duplicating it during the road test.

   • The problem must be directly related to road speed of the vehicle. The problem should not be affected by acceleration or deceleration, or may be reduced by coasting in NEUTRAL.
2. 2
   Refer to: Jacking and Lifting – Overview (100-02 Jacking and Lifting, Description and Operation).
3. 3
   • Inspect the driveshaft for damage, paint or incorrectly installed U-joints. Rotate the driveshaft slowly by hand and feel for binding or axial play in the U-joint yokes or CV joints. Remove the driveshaft. Clean the driveshaft if necessary. Install a new driveshaft if damaged. After installing any repairs or new components, recheck the vibration at road test speed.
   • If the vibration remains after inspection, measure the driveshaft runout.

   

Check

1. 1
   • Measure and check against the specified maximum value. Install the dial indicator with holding fixture. Rotate the propeller shaft by turning the axle, and measure the runout at the front, center and rear of the propeller shaft. For a multi-piece propeller shaft, measure each section at the front, center and rear.

   1. If the runout exceeds specification at the center of the front or center section of the rear tube, install a new driveshaft.
      REFER TO: Specifications (205-01 Driveshaft, Specifications).
      Use Special Service Tool: 100-002 (TOOL-4201-C) Holding Fixture with Dial Indicator.

   2. If the front and center sections are within specification but there is no rear runout, mark the high point of the rear runout with an index mark and go to step 2.
      REFER TO: Specifications (205-01 Driveshaft, Specifications).

   3. If the runout is within specification at all points, recheck the vibration at road test speed. If the vibration persists, balance the driveshaft. Refer to Driveshaft Balancing in this procedure.
      REFER TO: Specifications (205-01 Driveshaft, Specifications).

   

2. 2
   • Mark the driveshaft on the pinion seal lip. Disconnect the driveshaft and rotate it 180 degrees. Reconnect the driveshaft. Recheck the runout at the rear of the driveshaft.

   1. If runout still exceeds the limit, mark the high point and proceed to step 3.

   2. If runout is within specification, check the vibration at test speed. If vibration is still present, balance the propeller shaft. Refer to Propeller Shaft Balancing in this procedure.
3. 3
   • Excessive driveshaft runout may be caused by the driveshaft itself or by the pinion stem. To locate the source, compare the 2 high points determined earlier.

   1. If the index marks are located close together, within 25 mm (1 in), the propeller shaft is eccentric. Install a new propeller shaft.

   2. If the marks are on opposite sides of the driveshaft when rotated 180 degrees apart, the pinion stem is responsible. Check the pinion stem runout. If the pinion stem runout exceeds specification, a bent pinion is indicated.

   3. If the pinion runout is within specification, road test and check the vibration at road test speed. If the vibration persists, balance the driveshaft. Refer to Driveshaft Balancing in this procedure.

   

Driveshaft Balancing – Using Mastertech® MTS 4000 Balancer and NVH Analyzer (Vetronix)

1. 1
   Special Service Tool(s): Mastertech® Series MTS 4000 Transmission Balancer and NVH Analyzer (Vetronix) 257-00018. Working under the vehicle, install the accelerometer. The accelerometer can be connected and installed adjacent to the transmission or the driveshaft differential.
2. 2
   • Clean the area of the driveshaft and install reflective tape, then install the photo-tachometer sensor. The sensor should be positioned at approximately a 20-degree angle from perpendicular to the surface of the reflective tape. Make sure the sensor does not move during the balancing procedure.

   1. Reflective tape.

   2. Photo-tachometer sensor.

   

3. 3
   Special Service Tool(s): Mastertech® Series MTS 4000 Transmission Balancer and NVH Analyzer (Vetronix) 257-00018. Run the driveshaft balance test with the unmodified driveshaft.
   Use Special Service Tool: 100-002 (TOOL-4201-C) Holding Fixture with Dial Indicator.

Vehicles without Threaded Yoke Flanges

1. 1
   • Special Service Tool(s): Mastertech® Series MTS 4000 Transmission Balancer and NVH Analyzer (Vetronix) 257-00018. Run the second test with a test weight. Using metal tape, secure the test weight to the end of the driveshaft tube. The weight must be located at the end of the driveshaft tube as close as possible to the weld between the tube and the yoke. Mark the position of the test weight on the driveshaft, as shown in the illustration below.

   1. Test weight.

   2. Weld between tube and yoke.

   3. Pinion stem and CV joint inner race.

   • Select the test weight according to the driveshaft size. Larger driveshafts require 10 g (0.353 oz). Smaller driveshafts use 5 g (0.176 oz).

   

2. 2
   • Remove the test weight, then install the recommended weight at the position indicated by the Mastertech® Series MTS 4000 Transmission Balancer and NVH Analyzer (Vetronix). Using metal tape and epoxy, secure the balance weight to the driveshaft, as shown in the illustration below.

   1. Test weight.

   2. Measure in this direction.

   3. Driveshaft diameter.

   4. Direction of rotation.

   5. Balance weight relative to the centerline of the test weight.

   • Results are displayed relative to the location where the test weight was placed.

   

All vehicles

9. Special Service Tool(s): Mastertech® Series MTS 4000 Transmission Balancer and NVH Analyzer (Vetronix) 257-00018. Run the third test to confirm the repair.

Driveshaft Balancing – Clamp Method

1. 1
   Install 1 or 2 hose clamps on the driveshaft near the rear. The position of the clamp head(s) may be determined by trial and error.
2. 2
   Mark the rear of the driveshaft into 4 equal sectors and number the marks 1 to 4. Install the clamp on the driveshaft with the head in position No. 1, as shown in the illustration below. Check for vibration at road speed. Recheck with the clamp at each of the other positions to find the position that shows minimum vibration. If 2 adjacent positions show the same improvement, place the clamp head between them.

   

3. 3
   If the vibration persists, add a second clamp at the same position and repeat the vibration check.

   

4. 4
   If no improvement is observed, position the clamps in opposite directions, at equal distances from the best position determined in Step 14. Separate the clamp heads by approximately 13 mm (1/2 in) and recheck for vibration at road speed.

   

5. 5
   Repeat the process with increasing separation until the best combination is found or the vibration is reduced to an acceptable level. The hose clamps will remain attached to the driveshaft after completing this balancing procedure.