Checking Rear Wheel Suspension

Information 

• The trailing arm and wheel bearing housing are safety-relevant components. Perform the test with extreme care and accuracy  .
• If in doubt, always replace the lower trailing arm and wheel bearing lousing  .

1. Perform front and rear suspension alignment  .

   > 449503 PERFORMING FRONT AND REAR SUSPENSION ALIGNMENT

   > WM, 4495TW SETTING VALUES FOR SUSPENSION ALIGNMENT

   1. 1.1  If the camber and toe values are OK  : Continue with See
   2. 1.2  If the camber and toe values are 1° outside the tolerance limit  : Continue from See
   3. 1.3  If the camber and toe values are within the tolerance limit and the customer complains that the steering wheel is shaking or vibrating  : Continue from See 

   Check for telltale signs of damage to the chassis: 

   Information 

   • Checks required from Step 2  .
   • First align the suspension  .
   • If the camber and toe values on the rear axle are 1° outside of the tolerance limit and one of the listed telltale signs is found, always replace the trailing arm and wheel bearing housing  .
2. Check lateral runout of the brake disc and wheel hub (components installed)  .

   > 465302 CHECK REAR BRAKE DISCS

   > 465502 CHECK REAR PSCB BRAKE DISCS

   > 465402 CHECK REAR PCCB BRAKE DISCS

   1. 2.1  Test steps for lateral runout of brake disc and wheel hub:
      • Result is OK: Continue with See
      • Result of brake disc lateral runout > specification  : Remove brake disc and check lateral runout of wheel hub (see above: Check brake discs/PSCB/PCCB brake discs).
      • Result of wheel hub lateral runout OK  : Replace installed brake disc.
      • Result of wheel hub lateral runout > specification  : See 
   2. 2.2 Replace lower trailing arm and wheel bearing housing on the affected side of the vehicle  .

      > 421119 REMOVING AND INSTALLING TRAILING ARM 

      > 425219 REMOVING AND INSTALLING WHEEL BEARING HOUSING 

      Remove and install brake disc variant installed in the vehicle.

3. Check threaded joint -2- (trailing arm joint on wheel bearing housing) for deformation and true running  .
   1. 3.1  The following step must be carried out before starting to check the components:
   2. 3.2  Remove trailing arm -1-  on the wheel bearing housing.

      Courtesy of PORSCHE CARS NORTH AMERICA, INC.

      Trailing arm on wheel bearing housing

   3. 3.3  Assessment:
      • Result is OK: Continue with See
      • Result is not  OK: Replace trailing arm and wheel bearing housing  .

      > 421119 REMOVING AND INSTALLING TRAILING ARM 

      > 425219 REMOVING AND INSTALLING WHEEL BEARING HOUSING 

4. Check bearing -2- in the wheel bearing housing -1-(trailing arm joint on wheel bearing housing) for breaks/cracks  .

   Courtesy of PORSCHE CARS NORTH AMERICA, INC.

   Bearing in wheel bearing housing

   1. 4.1  Assessment:
      • Result is OK: Check is complete. Complete the vehicle.
      • Result is not  OK: Continue with See 
   2. 4.2 Replace trailing arm and wheel bearing housing  .

      > 421119 REMOVING AND INSTALLING TRAILING ARM 

      > 425219 REMOVING AND INSTALLING WHEEL BEARING HOUSING 

5. Complete the vehicle.
6. Perform suspension alignment and make adjustments, if necessary.

   > 449503 PERFORMING FRONT AND REAR SUSPENSION ALIGNMENT

   > WM, 4495TW SETTING VALUES FOR SUSPENSION ALIGNMENT