Flexplate/Torque Converter Vibration Test

Flexplate/Torque Converter Vibration Test
Isolating Vibration

Notice: Some engine/transaxle combinations cannot be balanced in this manner due to limited clearances between the torque converter bolts and the engine. Ensure that the bolts do not bottom out in the lug nuts or the torque converter cover could be dented and cause internal damage.

To isolate and correct a flywheel or torque converter vibration, separate the torque converter from the flywheel to determine if vibration is in the engine or transmission.
1. With the engine at idle speed and the transmission in PARK or NEUTRAL, observe the vibration.
2. Turn the engine OFF.
3. Raise and suitably support the vehicle. Refer to Vehicle Lifting.
4. Mark the relationship of the converter to the flywheel.
5. Remove the bolts attaching the converter to the flywheel.
6. Slide the torque converter away from the flywheel.
7. Rotate the flywheel and torque converter to inspect for defects or missing balance weights.
8. Lower the vehicle.
9. With the engine at idle speed and the transmission in PARK or NEUTRAL, observe the vibration. Refer to Diagnostic Starting Point - Vibration Diagnosis and Correction.
10. Turn the engine OFF.

Indexing Torque Converter
To determine and correct a torque converter vibration, the following procedure may have to be performed several times to achieve the best possible torque converter to flywheel balance.
1. Raise and suitably support the vehicle. Refer to Vehicle Lifting.
2. Rotate the torque converter one bolt position.





3. Align the torque converter hub (2) in the engine crankshaft (3) and install the torque converter to flywheel bolts.
4. Lower the vehicle.
5. With the engine at idle speed and the transmission in PARK or NEUTRAL, observe the vibration. Repeat this procedure until you obtain the best possible balance.

Noise and Vibration Analysis
A noise or vibration that is noticeable when the vehicle is in motion MAY NOT be the result of the transmission.
If noise or vibration is noticeable in PARK and NEUTRAL with the engine at idle, but is less noticeable as RPM increases, the cause may be from poor engine performance.
^ Inspect the tire for the following:
- Uneven wear
- Imbalance
- Mixed sizes
- Mixed radial and bias ply

^ Inspect the suspension components for the following:
- Alignment and wear
- Loose fasteners

^ Inspect the engine and transmission mounts for damage and loose bolts.
^ Inspect the transmission case mounting holes for the following:
- Missing bolts, nuts, and studs
- Stripped threads
- Cracks

^ Inspect the flywheel for the following:
- Missing or loose bolts
- Cracks
- Imbalance

^ Inspect the torque converter for the following:
- Missing or loose bolts or lugs
- Missing or loose balance weights
- Imbalance