TT Bearing walked
03-28-2011, 09:47 PM
#16
We checked my car recently at Thomas' place and felt vibration at 3000 RPM as well. Both hot and cold in Park. Don't notice it so much while driving, but haven't been looking for it, and haven't noted whether it continues through the RPM range. My question is the same as Thomas'.... is it the motor mounts, TT, or both?
I have 70K on what the records show as the second set of motor mounts (replaced 10 yrs ago), and 32K on the third torque tube.
The engine rocks on engine acceleration, but doesn't rock at (slightly uneven) idle.
I understand that jacking the car up slightly and gently with a block of wood under the oil pan while the engine is running will give evidence of MM failure if the vibration goes away.
Is it also possible to isolate the vibration source by removing the flex plate and then running the engine? If it's still there, it's the MM; if not it's either the TT or the Torque Converter.
I have 70K on what the records show as the second set of motor mounts (replaced 10 yrs ago), and 32K on the third torque tube.
The engine rocks on engine acceleration, but doesn't rock at (slightly uneven) idle.
I understand that jacking the car up slightly and gently with a block of wood under the oil pan while the engine is running will give evidence of MM failure if the vibration goes away.
Is it also possible to isolate the vibration source by removing the flex plate and then running the engine? If it's still there, it's the MM; if not it's either the TT or the Torque Converter.
03-29-2011, 07:10 AM
#17
Former Vendor
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Hi Bill,
Recommend you do a visual inspection under the car.
While under the properly supported car look at:
1. The motor mounts should be inspected for collapsing. Do they look nice and high or squashed down? How close is the oil pan to the front cross member where the steering rack lives. If they are very close it means the motor mounts have collapsed.
2. Pull the flex plate and check for any forward bow of the flex plate before loosening the front pinch bolt. Then loosen the pinch bolt and watch for any movement. If you want you can then loosen the six bolts that hold the flex plate to the flywheel and pull the flex plate back to disconnect the engine from the TT and check it as you already suggested.
3. Look down the TT toward the transmission and see how far the first bearing is from the bell housing side. Anything further than 10-15 inches means it has moved backward too much and is allowing the drive shaft to vibrate under load.
4. Pull out the little rubber plug at the rear of the TT and look in there. Check that the bolt is tightened to 59 ft lbs. and that you can see it. If you see what looks like a rubber toy wheel through the hole, that means the vibration dampener has either come apart or the rear bearing has moved, or both.
From these steps you should be able to diagnose the vibration problem.
Good luck,
Recommend you do a visual inspection under the car.
While under the properly supported car look at:
1. The motor mounts should be inspected for collapsing. Do they look nice and high or squashed down? How close is the oil pan to the front cross member where the steering rack lives. If they are very close it means the motor mounts have collapsed.
2. Pull the flex plate and check for any forward bow of the flex plate before loosening the front pinch bolt. Then loosen the pinch bolt and watch for any movement. If you want you can then loosen the six bolts that hold the flex plate to the flywheel and pull the flex plate back to disconnect the engine from the TT and check it as you already suggested.
3. Look down the TT toward the transmission and see how far the first bearing is from the bell housing side. Anything further than 10-15 inches means it has moved backward too much and is allowing the drive shaft to vibrate under load.
4. Pull out the little rubber plug at the rear of the TT and look in there. Check that the bolt is tightened to 59 ft lbs. and that you can see it. If you see what looks like a rubber toy wheel through the hole, that means the vibration dampener has either come apart or the rear bearing has moved, or both.
From these steps you should be able to diagnose the vibration problem.
Good luck,