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Trans Brace & vibrations ?

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Old Dec 10, 2008 | 05:06 PM
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Default Trans Brace & vibrations ?

Just had new clutch installed - along with transmission brace as well as differential brace. Drove the car first time today - noticed VERY noticable driveline "vibration" as rpm rise - how do I figfure out if its the transmission brace or some issue with the torque tube not being aligned/whatever ...? Replace the trans barace with the oem?

It's the Pfdat trans brace - and I remember someone else taking out one that caused excessive vibrations/noise etc.?

Thank you for any help & suggestions
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Old Dec 11, 2008 | 02:06 PM
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Ive repaced my clutch, put a DTE trans brace in the car and last summer put in the Pfadt brace and did not get any vibes til the Pfadt brace was installed. I did have to remove the rear diff vibration dampener as the Pfadt would not fit unless this was removed. In case you dont know what I am referring to it is a roundish steel ball that is bolted to the left side of the rear Diff. I think that is mainly why I get some vibes but not that much that I cant live with. I think I may try and cut some of the material off this winter and reinstall the "ball" and see if the is some improvement. I have read somewhere in these threads that most cars do experience some vibes after the Pfadt install. Cheers hope this helps
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Old Dec 11, 2008 | 02:36 PM
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Originally Posted by 1stGlance
Just had new clutch installed - along with transmission brace as well as differential brace. Drove the car first time today - noticed VERY noticable driveline "vibration" as rpm rise - how do I figfure out if its the transmission brace or some issue with the torque tube not being aligned/whatever ...? Replace the trans barace with the oem?

It's the Pfdat trans brace - and I remember someone else taking out one that caused excessive vibrations/noise etc.?

Thank you for any help & suggestions
Does it vibrate at idle (car stationary)?
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Old Dec 11, 2008 | 03:21 PM
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I've seen this type of vibration at high rev's after a trans. was replaced. I'm 99% sure it was (vibration) caused by a faulty or defective TORQUE CONVERTER because i tried 'indexing' the flywheel in every position possible, it didn't help much at all.. (you could try indexing the flywheel: remove all bolts, turn position of t.c. so the flywhl & t.c. now match up in different location) do this as many times as you have bolts on flywheel, turning one position each time, test driving in identical manner each time (hard accell. through top of 3rd gear) as vibration was felt at top of 2nd & 3rd) if indexing does nothing, concider replacing Torque Converter - see next post...
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Old Dec 11, 2008 | 03:23 PM
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Originally Posted by timg2003
I've seen this type of vibration at high rev's after a trans. was replaced. I'm 99% sure it was (vibration) caused by a faulty or defective TORQUE CONVERTER because i tried 'indexing' the flywheel in every position possible, it didn't help much at all.. (you could try indexing the flywheel: remove all bolts, turn position of t.c. so the flywhl & t.c. now match up in different location) do this as many times as you have bolts on flywheel, turning one position each time, test driving in identical manner each time (hard accell. through top of 3rd gear) as vibration was felt at top of 2nd & 3rd) if indexing does nothing, concider replacing Torque Converter - see next post...
Did you miss the part about the OP just replacing the clutch?
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Old Dec 11, 2008 | 03:23 PM
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On the Vette I worked on (Torque Converter Vibration) -- what happened in the end BEFORE I figured out the cause of the vibration at high revs, was that the T.C. 'CRACKED!!' - Yes, it cracked about 2" long at the outer perimeter & expelled alot of trans. fluid very quickly. MESSY!!.
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Old Dec 11, 2008 | 04:46 PM
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Originally Posted by lucky131969
Does it vibrate at idle (car stationary)?
no doesn't seem to will need to check again to be sure
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Old Dec 12, 2008 | 01:57 PM
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Originally Posted by 1stGlance
Just had new clutch installed - along with transmission brace as well as differential brace. Drove the car first time today - noticed VERY noticable driveline "vibration" as rpm rise - how do I figfure out if its the transmission brace or some issue with the torque tube not being aligned/whatever ...? Replace the trans barace with the oem?

It's the Pfdat trans brace - and I remember someone else taking out one that caused excessive vibrations/noise etc.?

Thank you for any help & suggestions
The Pfadt Trans brace won't cause a vibration, what happens is the factory mount masks the problem. A lot of aftermarket clutches are very unbalanced out of the box, you'd think they would be right on considering they are a performance product. The factory mounts will often hide or mask this problem but the underlying problem is still present.

The Pfadt brace removes unwanted deflection from the system, we've only had a few issues and each time an aftermarket clutch was present, torque tube bushings were worn out or the drive shaft was out of balance. We do offer softer bushings and pads for the mount and this will help but again in a perfectly balanced system vibrations aren't present.

Please feel free to call or email us anytime, we're always here to answer questions and offer solutions.

Happy Holidays!

Jordan
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Old Dec 12, 2008 | 02:31 PM
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Originally Posted by jordan@pfadtracing
The Pfadt Trans brace won't cause a vibration, what happens is the factory mount masks the problem. A lot of aftermarket clutches are very unbalanced out of the box, you'd think they would be right on considering they are a performance product. The factory mounts will often hide or mask this problem but the underlying problem is still present.

The Pfadt brace removes unwanted deflection from the system, we've only had a few issues and each time an aftermarket clutch was present, torque tube bushings were worn out or the drive shaft was out of balance. We do offer softer bushings and pads for the mount and this will help but again in a perfectly balanced system vibrations aren't present.

Please feel free to call or email us anytime, we're always here to answer questions and offer solutions.

Happy Holidays!

Jordan
The prospect of having go through another clutch install does not bring any joy Especially when I have to pay a shop to do that....

To determine that it is the clutch - or at lest not the brace is only slightly time consuming - but after that?
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Old Dec 12, 2008 | 03:07 PM
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Originally Posted by 1stGlance
The prospect of having go through another clutch install does not bring any joy Especially when I have to pay a shop to do that....

To determine that it is the clutch - or at lest not the brace is only slightly time consuming - but after that?
The factory rubber mount will absorb most of the vibration, the issue will still be there. At least you won't have to R&R the clutch to have it balanced. The trans brace should have come with the street bushings for the center of the mount? When did you purchase it? Please email your address to me and I'll mail you the softer outer pads which will be an easy swap.

The fact that the vibration gets worse with RPM is a sign something is out of balance. What clutch are you using? We're the torque tube bushings replaced when this work was taking place? I've been told by many that aftermarket clutch assembly must be balanced even if they state they are.

If there is anything I can help with please call or email. I've been there and done it, it isn't fun.....

Jordan
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Old Dec 12, 2008 | 05:35 PM
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Originally Posted by 1stGlance
no doesn't seem to will need to check again to be sure

YES vibrates at idle.
Today I got in after letting sit overnight - so it was cold. When I pushed the clutch in made strange noises - like something was rubbing / clattering around. This noise seemed to diminish after I drove it and it warmed up. But the vibration is still there...
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Old Dec 12, 2008 | 05:53 PM
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Originally Posted by 1stGlance
YES vibrates at idle.
Today I got in after letting sit overnight - so it was cold. When I pushed the clutch in made strange noises - like something was rubbing / clattering around. This noise seemed to diminish after I drove it and it warmed up. But the vibration is still there...
Sounds like clutch/flywheel balance
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Old Dec 12, 2008 | 06:17 PM
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Originally Posted by jordan@pfadtracing
The factory rubber mount will absorb most of the vibration, the issue will still be there. At least you won't have to R&R the clutch to have it balanced. The trans brace should have come with the street bushings for the center of the mount? When did you purchase it? Please email your address to me and I'll mail you the softer outer pads which will be an easy swap.

The fact that the vibration gets worse with RPM is a sign something is out of balance. What clutch are you using? We're the torque tube bushings replaced when this work was taking place? I've been told by many that aftermarket clutch assembly must be balanced even if they state they are.

If there is anything I can help with please call or email. I've been there and done it, it isn't fun.....

Jordan

Thank you and much appreciated - I'm feeling certin now that it is indeed the clutch. I was under the impression that I was getting a clutch and flywheel (balanced) replacement - but sounds like only the clutch got replaced. Its a SPEC stage-3.
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Old Dec 12, 2008 | 06:39 PM
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Burk,

I would highly suggest that you check here on the forum or locally for someone that can balance your engine with the proper equipment. I've done many, and the whole process only takes about an hour. It will also identify what the true problem is. Don't rule out the mount, which could be allowing excess vibration through.

Originally Posted by jordan@pfadtracing
The Pfadt Trans brace won't cause a vibration, what happens is the factory mount masks the problem.
Jordan,

As far as your statement that the stock mount “mask the problem”. That is exactly what a mount's job is. Vibration isn't a problem as long as the mount keeps vibration from transferring to other structures. Factory mounts for engines and transmissions are tuned for isolating normal system vibrations. What are the Pfadt's tuned to?

Originally Posted by jordan@pfadtracing
We do offer softer bushings and pads for the mount and this will help but again in a perfectly balanced system vibrations aren't present.
Have you ever seen a “perfectly balanced system”? Fact is, if you did, you would need an elastomer mount at all, it could be solid mounted, but I'm sure you know there isn't such a thing.

Regards, and hope everone has a great Christmas and Happy New Year!

Eric D
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