vibration-help or opinions needed

I'm in the Palm Springs area,across the country from you,but I might take you up on the offer and pay shipping? Not to mAny of these cars in my area that I know of. I'm going to call turbo Lou tomorrow . I love these cars but this one is makin it hard lol.
 
I'm in the Palm Springs area,across the country from you,but I might take you up on the offer and pay shipping? Not to mAny of these cars in my area that I know of. I'm going to call turbo Lou tomorrow . I love these cars but this one is makin it hard lol.
That would probably cost you $100 round trip hate to see you waste the money. Im sure somebody within reasonable distance has one. Lets see if anybody closer chimes in. Worse case scenario I'll do it but I'm sure theres others out there that wont cost you so much freight.

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Still chasing it,I did rule out engine and tourqe converter due to the fact that when the vibration occurs I can drop it in neutral and the vibration remains. I'm focusing on the chatter marks you see on the yoke in the pictures. That was the old yoke. The same marks are on the new yoke, I don't like to think this way but I'm suspecting the drive shaft that has been built and balanced by two different shops.I'm trying to find a known good shaft to try but I know no one with a turbo regal. Thanks for checking in and for the time you took to talk to me the other day. Like you said I missed something
 
If you install hose clamps around the driveshaft, the screw part will act as a weight. You can then put perhaps two on
and see if it helps or hurts the situation. You can mark the shaft and rotate the clamps around the shaft to experiment.
If it neither makes to improvement or makes it worse, it's not the drive shaft.
The drive shaft would vibrate at a frequency much higher than the wheels.
If you could somehow find what frequency you are feeling, it can help identify where the vibration is coming from.
 
update.took the driveshaft to a reputable shop and they said it was terrible work,and built me a alluminum shaft for the price i paid to have the steel one built and vibration is still there!better but still there. so after some thought and getting the key phrase that vibrations are never predictable i want to elimnate the convertor but before i buy a new one i would like to swap in another to try. so anyone in the socal area that would be willing to ship me there known good d5 on loan??
 
i'm going to follow thes thread as I've been fighting this same issue for years with no luck.
I still think it's something between the flexplate and the output shaft
thanks Mike
 
Vibrations usually have several causes in combination. You just have to work through all possibilities till you resolve it. As previously said, low speed vibrations are usually driveshaft related while high speed vibrations are usually wheel and tires. I chased a high speed vibration (75-80 mph) until I had the wheels/tires DYNAMICALLY balanced. Some tire places just do a static balance. It makes a big difference. That removed 50% of the issue. I also suspected my PI converter, but that wasn't it. I finally found the offending issue: Flexplate. I had a B&M flexplate that was 29.1 rated. Thought it was good quality, but turns out it had runout and was out of balance. Replaced it with a TCI 29.1 rated flexplate. Vibration moved a bit lower (72-77) but still there. That one also had runout! Finally spent the money on an ATI flexplate. Pricey but man do they make good products! Installed it and put dial indicator on it. I could not measure ANY runout. That thing was as flat as they come. They also balance them to an exceptional level. Vibration is history.

The marks on your yoke suggest pinion angle issues or rear wheel imbalance transmitting through driveline. Start with the easy stuff like a dynamic wheel balance of all four wheels. See if that helps. If not solved, work through the remaining things you haven't touched yet.

Also when balancing a driveshaft, high speed balancing is important. Most shops only do low speed balancing. You would be surprised what a difference that can make.
 
Any luck with this issue I have the same issue 55mph and up. Going to have tires
Rebalanced tomorrow.
 
Any luck with this issue I have the same issue 55mph and up. Going to have tires
Rebalanced tomorrow.
You should make your own thread. But did you run it on jack stands to 55 mph? If it still vibrates the problem is one of those moving parts. Then the rear tires can be ruled out by taking them off put lug nuts back on drums. If problem goes away it's wheel balance or bent rim. You can also put the front tires on and test them back there.
I love this test because the tires have a large moment of inertia and are easily ruled out or in with this simple test. ( 99% of the time)
 
You should make your own thread. But did you run it on jack stands to 55 mph? If it still vibrates the problem is one of those moving parts. Then the rear tires can be ruled out by taking them off put lug nuts back on drums. If problem goes away it's wheel balance or bent rim. You can also put the front tires on and test them back there.
I love this test because the tires have a large moment of inertia and are easily ruled out or in with this simple test. ( 99% of the time)
Not exactly. You are not feeling or measuring road force on jackstands so tire / wheel uniformity is still in question. You could have a tire that has a high spot, or a uniformity issue under load which is perceived as a vibration. The only way to measure this is to use a road force balancer which loads the tire wheel assembly with upwards of 1200 lbs and measures this. Then sheen dimensions are measures and a prediction is made to see if you can match the high / stiff spot in the tire to the lowest spot on the wheel. Also while I'm on my soapbox make sure the shop measuring Balance and road force is at a minimum using collets from the back. The best method for centering wheels is a collet on the back side of the wheel and a flange plate on the front. I would not accept a shop using a traditional cone and coning the front side of the wheel. Most shops do it this way because they don't know any better, and or they are lazy. Front coning also puts the cone on the threaded part of the balancer shaft which wears significantly faster than the solid part. This introduces even further inaccuracies. If the wheels aren't centered on the balancer correctly your pissing in the wind.

Edit: quick test to see if your centered, when all balanced take it off, and put it back on the balancer. Spin again. If balance changes you are not repeating which means you are not centered

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Not exactly. You are not feeling or measuring road force on jackstands so tire / wheel uniformity is still in question. You could have a tire that has a high spot, or a uniformity issue under load which is perceived as a vibration. The only way to measure this is to use a road force balancer which loads the tire wheel assembly with upwards of 1200 lbs and measures this. Then sheen dimensions are measures and a prediction is made to see if you can match the high / stiff spot in the tire to the lowest spot on the wheel. Also while I'm on my soapbox make sure the shop measuring Balance and road force is at a minimum using collets from the back. The best method for centering wheels is a collet on the back side of the wheel and a flange plate on the front. I would not accept a shop using a traditional cone and coning the front side of the wheel. Most shops do it this way because they don't know any better, and or they are lazy. Front coning also puts the cone on the threaded part of the balancer shaft which wears significantly faster than the solid part. This introduces even further inaccuracies. If the wheels aren't centered on the balancer correctly your pissing in the wind.

Edit: quick test to see if your centered, when all balanced take it off, and put it back on the balancer. Spin again. If balance changes you are not repeating which means you are not centered

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See where I said 99%

Most shops don't even do the second spin. That's the bulk of the trouble. They knock the weight where they think it showed and don't retest for zero.
 
Well my experience differs. I would guess 30% or more of assemblies can be optimized for radial force variation and probably 15% or more actually have perceivable vibrations even though they balance perfectly. Balance and road force variations are 2 completely different things. My point was spinning tires in the air does absolutely nothing to diagnose a road force variation issue. If you think that only accounts for 1% of the customer vibration complaints you would be very mistaken.

None of this applies to the OPs car though since he has the vibration even with the wheels removed. I just wrote this because throwing the front tires on the rear to check balance just isn't the tell all and I wanted people to know that. Vibrations can be a pain in the ass to troubleshoot.

What is the status of this thread? Is the OP car fixed? Can we get a list of everything checked / done.

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Well my experience differs. I would guess 30% or more of assemblies can be optimized for road force variation and probably 15% or more actually have perceivable vibrations even though they balance perfectly. Balance and road force variations are 2 completely different things. My point was spinning tires in the air does absolutely nothing to diagnose a road force variation issue. If you think that only accounts for 1% of the customer vibration complaints you would be very mistaken.

None of this applies to the OPs car though since he has the vibration even with the wheels removed. I just wrote this because throwing the front tires on the rear to check balance just isn't the tell all and I wanted people to know that. Vibrations can be a pain in the ass to troubleshoot.

What is the status of this thread? Is the OP car fixed? Can we get a list of everything checked / done.

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Thank you for all the info. Sorry I did not mean the hijack someone's thread!
I was looking to see if he fixed his issue and what was the cause. Finding a good tire shop that takes the time and effort to do the balance correctly is very hard to fine.
 
I removed tires from rear. With drums on vibration was still there and even worse than tires on shook the whole car! I put it in reverse and at high speed there was little to no vibration?
 
Sorry I haven't updated. After my last post I had the vigilante rebuilt by Dave husek and the vibration is still there. I still believe it's originating from the rear half of the trans. Maybe a worn output shaft? If you've read from the beginning the trans was rebuilt recently with quality parts. He had no way to spin any of the internals as it seems most trans shops don't. They will only quote to replace the back half internals at the price of over 2k. I have no more time or money too invest,so the car is in the for sale section. If you read from the beginning you'll see all things that were done. Thanks again for the advise/opinions
 
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