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Driveshaft vibrations

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Old Sep 22, 2010 | 09:03 PM
  #1  
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bail315
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From: Colorado
Default Driveshaft vibrations

I just had a set of 4:10’s installed in my ‘06 GT 5 speed. The issue is when I hit 60mph I get vibrations coming from the driveshaft. The vibrations continue up to 65mph and the quite down. I would not describe them as severe. It sounds more like bass through a subwoofer. I haven’t taken it past 80mph so I don’t know if they come back at higher speeds. I’ve read this is a common problem with changing gears but there doesn’t seem to be a consensus on solutions. I don’t fully understand why changing the gears would result in vibrations. I’ve had driveshaft issues with Jeeps in the past but that was a result of altering the pinion angle with suspension mods. Has anybody had the same issue and found a solution?

Thank you!
Old Sep 22, 2010 | 09:30 PM
  #2  
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The reason sometimes get driveshaft vibe after getting gears is that now, for a given speed your driveshaft is spinng much faster. At 60mph it is spinning as fast as it would have been at like 90 or 100 mph with the stock gears, depending on gears you had stock... mine has 3.31 gears stock.
Solution: the are some places that can balance your driveshaft (have to take it out of the car first). Your just have to hunt around in your area to find one. If that does not work, or if you choose not to go that route, only other solution is to get an aftermarket driveshaft. But even then, sometimes folks have issues.
I had the same issue when I had 3,73 gears put in, but my vibration was around 70mph. I just ordered me a Coast aluminum DS and it pretty much cured the problem. By pretty much, I mean I still get a slight vibration issue, but it is around 90mph, and I don't typically cruise at that speed for long anyway, so it's a not an issue. Hope this helps..
Old Sep 23, 2010 | 06:11 PM
  #3  
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I had the same problem after installing 4.10's. Had a new drive shaft put in under warranty and all that did was move the vibration from one speed to another. After much research, I found out many people had good results with removing the rear of the drive shaft and turning the shaft 180 degrees. I did that and was very careful to torque the pinon flange bolts to the proper torque value as well as tighten the bolts in a star pattern. This solved my vibration completely. I don't think the orientation of the shaft is as important as properly tightening the flange bolts. I tried having the dealer turn the shaft, but it did not work. Probably because they don't take the time to properly tighten the Flange bolts.
Old Sep 25, 2010 | 08:52 PM
  #4  
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bail315
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Thank you for the advice! I had time to crawl underneath the car this evening and get some work done on it. Since I was there I figured I would try reversing the driveshaft 180 degrees. When putting it back on I was also very careful to torque the bolts in a star pattern. I can definitely see an issue if they are not tightened in a proper sequence. After finishing up I took it out on the highway and I am vibration free! I took it up to 90 without any problems. If there are vibes faster than that I’m not to worried as I don’t have many opportunities to drive much faster. Thanks again! The 4:10 gears were definitely worth it.
Old Sep 26, 2010 | 06:08 AM
  #5  
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I have a similar symptom with my Al DS. Im on my 3rd gear set (4.10s) and it made the same noise with all 3. Only noticable on te highway at cruising speed. sounds like a cyclical humming noise, only when on the gas, dies out when I let off. It appears to go away with more speed, or if i let off and coast down to a lower speed. It is definitely only in a certain range. Goes away immediately when i engage the clutch.

So it would seem its an imbalance in the driveshaft. I have tried rotating its orientation to no avail. The sound is liveable, but its there. I did have some aftermarket LCAs/UCA/Relocation brackets, and these components with their poly bushings only amplified the unwanted sound.

1000's of miles later its still the same.
Old Sep 28, 2010 | 09:46 AM
  #6  
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Originally Posted by Surreal
I have a similar symptom with my Al DS. Im on my 3rd gear set (4.10s) and it made the same noise with all 3. Only noticable on te highway at cruising speed. sounds like a cyclical humming noise, only when on the gas, dies out when I let off. It appears to go away with more speed, or if i let off and coast down to a lower speed. It is definitely only in a certain range. Goes away immediately when i engage the clutch.

So it would seem its an imbalance in the driveshaft. I have tried rotating its orientation to no avail. The sound is liveable, but its there. I did have some aftermarket LCAs/UCA/Relocation brackets, and these components with their poly bushings only amplified the unwanted sound.

1000's of miles later its still the same.
I have this exact same problem but I have a stock driveshaft. It starts at about 45 MPH and dies away after 60 MPH. A low volume cyclical humming noise only when on the gas. It’s a separate noise from regular exhaust drone. It does not matter what gear I am in, it always happens at the same speed.

I had my gears done 6 months ago, and this just started a few weeks back unless somehow I just never noticed before. I’ve not brought it to the shop, and after seeing you’re on your third gear set trying to address the same problem I’m not sure I’m inclined to bother at this point!

Can anyone say if this might cause any long term damage if left unchecked? If no then it’s not worth messing with. It’s not really bothersome and not louder then exhaust, road noise or any other noises the car makes at speed, it’s just another noise.

Tim
Old Sep 28, 2010 | 04:29 PM
  #7  
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From: NH
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hmm interesting, you get it with the stock 2pc ds? hmm what else could it be then? I originally thought it was only at one speed, but I found that it does it not just in 5th, but 4th and 3rd as well, right around 2k rpm
Old Sep 29, 2010 | 08:24 PM
  #8  
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Originally Posted by Surreal
hmm interesting, you get it with the stock 2pc ds? hmm what else could it be then? I originally thought it was only at one speed, but I found that it does it not just in 5th, but 4th and 3rd as well, right around 2k rpm
Yup, 2pc ds and no ideas!

Tim
Old Sep 30, 2010 | 11:06 PM
  #9  
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Hey,
I just installed a 9+ in my car. It is all brand new from Currie. See parts list below. I took car into them to go for a drive and Tony drove it. He said for sure the gears are making noise on accelerating and decelerating. He offered to take apart and look at it again. But he also said that a guy with a 2006 Mustang that work at Currie just put a 9+ in his car the other day and it is making noise as well with 3:50 gears.
Tony and Travis said he also had an after market Upper control arm like I have. They told me it might be the upper control arm and the Johnny joint making the noise of gears amplify and suggested I check that first.
I want to see if any of you have experience with this and know of any fixes or is it just a bad gear install from Currie. If it is Currie said they will fix, but hate to take it out again if it is the upper control arm. Only to install again with same noise.
Old Oct 1, 2010 | 04:18 AM
  #10  
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From: NH
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if your gears are FRPP they shouldnt make any noise at all, the 4.10s I have in now have never made any sounds at all. Just noticed you have motive gears...they tend to make noise from what I have heard.



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