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Th400 Installed Now Bad Vibration

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Old Jun 17, 2007 | 09:10 PM
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Default Th400 Installed Now Bad Vibration

The T56 was just swapped out for the TH400 and now there is a bad vibration going on at/near 3500 rpms. It feels like the whole car is pulsing. When all of that went in so did a new Spohn Torque arm, new driveshaft etc. I know that the builder used a spacer to mount a non-ls1 converter as well. There really wasn't anything out of the ordinary.

It shakes like crazy. I didn't have this issue before or at least didn't notice it with the M6.

Where would you startlooking? The tranny is also leaking a bit of fluid from the dust cover area and I don't know if that matters or not (for the vibration)
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Old Jun 17, 2007 | 09:17 PM
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maybe the front pump bushing went out.....
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Old Jun 18, 2007 | 06:30 AM
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are you talking about the leak or the vibration (or both)?
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Old Jun 18, 2007 | 11:58 AM
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WIll it vibrate in Neutral, without the entire drivetrain rotating?

If so, then I would definately look for an imbalance at the converter / flexplate area.

g
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Old Jun 18, 2007 | 12:04 PM
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sounds like an harmonics. an old trick is to put 2 hose clamps on the shaft. run the car on jack stands. run until the shake is there and note the rpm. then move the clamps around and away from each other and repeat test. if you don't understand call me 818 676 4480 john
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Old Jun 18, 2007 | 12:24 PM
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So that would just test for an imbalanced shaft then?
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Old Jun 19, 2007 | 07:27 AM
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I took it out last night put it in neutral and it really didn't make any of the vibrations. I guess the driveshaft is next. Hopefully that is it.
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Old Jun 19, 2007 | 07:32 AM
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Might want to check the pinion angle.
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Old Jun 19, 2007 | 08:28 AM
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Make sure that the yoke is not bottoming out putting the driveshaft into a bind.

g
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Old Jun 19, 2007 | 08:33 AM
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I agree on pinion angle.
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Old Jun 22, 2007 | 01:22 PM
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You had to replace the driveshaft right? My new driveshaft from Strange was severely out of balance. Had it balanced and all vibration went away.
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Old Jun 23, 2007 | 05:15 PM
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balanced mine twice,strange huh
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