the f-ing vibration
12-20-2009, 10:58 AM
#1
the f-ing vibration I need ideas. I cant figure this thing out. I have a vibration in the car I can not get rid of. I've posted on this before, but nothing has fixed it.
It has had all tires balanced, its been aligned, new u-joints, new clutch and flywheel, new rotors. Where is the vibration? It doesnt really become noticable until 45-50 mph. Then continues up to around 65-70, goes away, then comes back around 75-80. Driveshaft? Anyone in the Atlanta area?
I think part of it comes from the exhaust because of the POS SLP catback. Anyone want to trade their Magnaflow? I feel alot of reverbiration (sp) from the exhaust, but its not causing the feeling when I'm driving that makes it feel out of balance.
It has had all tires balanced, its been aligned, new u-joints, new clutch and flywheel, new rotors. Where is the vibration? It doesnt really become noticable until 45-50 mph. Then continues up to around 65-70, goes away, then comes back around 75-80. Driveshaft? Anyone in the Atlanta area?
I think part of it comes from the exhaust because of the POS SLP catback. Anyone want to trade their Magnaflow? I feel alot of reverbiration (sp) from the exhaust, but its not causing the feeling when I'm driving that makes it feel out of balance.
12-20-2009, 12:19 PM
#2
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where do you feel the vibration? can you feel it through the gas pedal? is it constant, or does it sound rotational, like a wom..wom..wom? have you had your driveshaft balanced?
12-20-2009, 02:00 PM
#4
where do you feel the vibration? can you feel it through the gas pedal? is it constant, or does it sound rotational, like a wom..wom..wom? have you had your driveshaft balanced?
Just racking my brain, it really almost seems related to the load on the car. It almost like the reverbiration from a load on it makes it stand out. In 4th gear, everything is locked in and turning correct? Cause in 4th and just below 2k rpm, it is the most prominate in the shifter. At hi-way speeds, say over 70, you can almost call it a wom..wom... as it comes and goes at regular intervals, just a few seconds apart. Could the internals in the tranny be at fault?
12-20-2009, 02:25 PM
#5
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well i would get your driveshaft checked out anyway. i was feeling the vibration through the gas pedal and i got mine checked out and it was bad bent. and its not that expensive, $80 i think. like jsteele90 said, if you have a poly mount, through a new stock one back in.
12-20-2009, 11:46 PM
#6
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Put it in neutral on the highway when it's doing it. Mine did something similiar, would go away when I put it in neutral. It did end up being enternal with the trans. Not sure what. Got it rebuilt and the vibration was gone. I chased it forever as well.
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12-21-2009, 01:46 AM
#9
It doesnt seem to be coming through the gas pedal. I feel it more in the shifter. It doesnt seem to be RPM related. I would say more constant, not a wom,wom. Never had it balanced, but I would like to. Just gotta figure out where I would get that done around here. I replaced the stock trans mount with the poly mount because the oem was broken when I bought it.
Just racking my brain, it really almost seems related to the load on the car. It almost like the reverbiration from a load on it makes it stand out. In 4th gear, everything is locked in and turning correct? Cause in 4th and just below 2k rpm, it is the most prominate in the shifter. At hi-way speeds, say over 70, you can almost call it a wom..wom... as it comes and goes at regular intervals, just a few seconds apart. Could the internals in the tranny be at fault?
Just racking my brain, it really almost seems related to the load on the car. It almost like the reverbiration from a load on it makes it stand out. In 4th gear, everything is locked in and turning correct? Cause in 4th and just below 2k rpm, it is the most prominate in the shifter. At hi-way speeds, say over 70, you can almost call it a wom..wom... as it comes and goes at regular intervals, just a few seconds apart. Could the internals in the tranny be at fault?
If you want to see and hear the vibration find a drive on lift with optional jacks to jack the rear end off of the lift. Start and run the car on the lift with the rearend jacked up off of the lift. You will be able to hear and see where the noise is comming from.
If the new mount isn't exactly the same height as the stock mount it is possible to get vibration at the front u-joint. Just a half inch up or down on the transmission can cause the front j-joint to vibrate.
The poly mount won't absorb as much as the rubber mount, as a result you get noise transmitted up through the console.
Check your pinion angle too. If the angle on the front u-joint changes - in most cases you need to reset the rear angle to account for the change made to the front u-joint. The wrong height transmission mount will change the ds angle at the front u-joint.
12-22-2009, 10:07 PM
#10
Sounds stupid but long story short, make sure your rear bumper cover is secured at all attach points. Be sure to check your air dam for the same along with any kind of horizontal rips/cracks. I agree with the above that its most likely your tranny internals but i've had a similar experience with a 99 t/a that was kickin my ***. Turned out to be an f'd up air dam flapping in the wind!
12-24-2009, 07:54 PM
#12
Replacing the poly mount with the stock one almost seems like a waste. I replaced it because the stock one broke, which they apparently do fairly often.
I did notice that when driving home, it almost seems like when turning on the highway, traveling around 70-75 going around the curve, the vibration goes away? But if the car was aligned and it didnt go away, wtf?
I will look around at the panels being loose, I have driven beside, in front, and behind it while it was going down the highway and I dont remember seeing anything flop.
I did notice that when driving home, it almost seems like when turning on the highway, traveling around 70-75 going around the curve, the vibration goes away? But if the car was aligned and it didnt go away, wtf?
I will look around at the panels being loose, I have driven beside, in front, and behind it while it was going down the highway and I dont remember seeing anything flop.
12-25-2009, 03:18 AM
#14
Agree - considering that there are perhaps hundreds of posts confirming the fact that the poly mount enhances vibration in the drivertrain.
+ a stock mount is pretty cheap and inexpensive to replace even if they don't last very long.
Replacing with a stock mount would confirm too - if that is the cause.
+ a stock mount is pretty cheap and inexpensive to replace even if they don't last very long.
Replacing with a stock mount would confirm too - if that is the cause.
12-25-2009, 03:51 PM
#15
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Look at your driveshaft balancing weights. It's not uncommon for a weight to get slung off. There were be a noticeable spot where a weight used to be if one is missing.
I'd look at that and then my next step would be to change the transmission mount.
Reach down and check the crank bolt in the balancer too.
These are all simple cheap things to try.
I'd look at that and then my next step would be to change the transmission mount.
Reach down and check the crank bolt in the balancer too.
These are all simple cheap things to try.
12-26-2009, 12:10 PM
#17
This causes the angle of the u-joint on the front of the driveshaft to be opposite of the angle on the rear of the driveshaft. This also changes pinion angle.
On my car - just a half inch caused vibration. I shimmed it and it went away.
Put your car on a lift - put it in gear - you can see and hear the vibration at the front of the driveshaft.
12-26-2009, 01:09 PM
#19
I had a vibration on my car after upgrading to a poly mount as well. Comparing it to the stock mount I found the poly piece was 1/8" shorter. I shimmed the mount and the vibration went away. My vibration was in the exact same speeds you posted and I bet your cause is also identical. I suggest you pick up a couple 1/8" thick fender washers and shim the mount between the tranny and upper part of the mount.
Btw: I have an adjustable torque arm and no amount of rear pinion adjustment resolved the vibration. I too tried countless things to remedy the problem before finding the mount was the wrong height. I have also suggested this fix to others with the same issue and it eliminated the vibration for them as well. There is a reason why there are hundreds of threads complaining about vibration with a poly mount and it is not due to the stiffness of the mount, it is incorrect pinion angle.
Btw: I have an adjustable torque arm and no amount of rear pinion adjustment resolved the vibration. I too tried countless things to remedy the problem before finding the mount was the wrong height. I have also suggested this fix to others with the same issue and it eliminated the vibration for them as well. There is a reason why there are hundreds of threads complaining about vibration with a poly mount and it is not due to the stiffness of the mount, it is incorrect pinion angle.
12-26-2009, 01:46 PM
#20
I had a vibration on my car after upgrading to a poly mount as well. Comparing it to the stock mount I found the poly piece was 1/8" shorter. I shimmed the mount and the vibration went away. My vibration was in the exact same speeds you posted and I bet your cause is also identical. I suggest you pick up a couple 1/8" thick fender washers and shim the mount between the tranny and upper part of the mount.
Btw: I have an adjustable torque arm and no amount of rear pinion adjustment resolved the vibration. I too tried countless things to remedy the problem before finding the mount was the wrong height. I have also suggested this fix to others with the same issue and it eliminated the vibration for them as well. There is a reason why there are hundreds of threads complaining about vibration with a poly mount and it is not due to the stiffness of the mount, it is incorrect pinion angle.
Btw: I have an adjustable torque arm and no amount of rear pinion adjustment resolved the vibration. I too tried countless things to remedy the problem before finding the mount was the wrong height. I have also suggested this fix to others with the same issue and it eliminated the vibration for them as well. There is a reason why there are hundreds of threads complaining about vibration with a poly mount and it is not due to the stiffness of the mount, it is incorrect pinion angle.
Somewhere there is a post about u-joint angles and the vibration that occurs when the front u-joint angle is more than 1 degree different than the rear.
In your case (an 1/8 of an inch) and in my case (1/2 inch) will cause way more than 1 degree difference in the angle of the front u-joint - and as a result cause the u-joints to be out of phase causing vibration.
I think in a lot of cases the poly mount purchased isn't even the correct part number or design - so obviously it might not be the correct height.
Thanks for posting your results too.
