Vibration from undercarriage
05-14-2007, 08:09 AM
#1
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Location: Eureka, Mo
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Vibration from undercarriage
I've only noticed it since I got my gears installed. Two or three times it has been pretty loud for 1-2 seconds, then goes away. Lately I have been listening VERY closely and I can just barely make out the sound of a vibration over the sound of my exhaust.
My first thought, when I first heard it when it was loud, was that something in the exhaust had got loose and was rattling. Now I'm thinking it is probably the driveshaft slightly out of balance.
What does an off balanced driveshaft sound/feel like? I don't feel any vibrations or anything, just hear it. Again, this was only noticed after my gears, and it is still not a real problem.
My first thought, when I first heard it when it was loud, was that something in the exhaust had got loose and was rattling. Now I'm thinking it is probably the driveshaft slightly out of balance.
What does an off balanced driveshaft sound/feel like? I don't feel any vibrations or anything, just hear it. Again, this was only noticed after my gears, and it is still not a real problem.
05-14-2007, 11:37 PM
#2
2nd Gear Member
Join Date: Sep 2006
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RE: Vibration from undercarriage
id have to say the easiest thing to check is the u joint angle. here's some stuff i pulled up:
High angles combined with high RPM is the worst combination, resulting in reduced u-joint life. Too large and unequal u-joint angles can cause vibrations and contribute to u-joint, transmission and differential problems. The improper u-joint angles must be corrected. Ideally, the operating angles on each end of the driveshaft should be equal to or within 1 degree of each other, have a 3 degree maximum operating angle and have at least 1/2 of a degree continuous operating angle.
Here's the web page: http://www.drivetrain.com/driveline_angle_problem.html
High angles combined with high RPM is the worst combination, resulting in reduced u-joint life. Too large and unequal u-joint angles can cause vibrations and contribute to u-joint, transmission and differential problems. The improper u-joint angles must be corrected. Ideally, the operating angles on each end of the driveshaft should be equal to or within 1 degree of each other, have a 3 degree maximum operating angle and have at least 1/2 of a degree continuous operating angle.
Here's the web page: http://www.drivetrain.com/driveline_angle_problem.html
05-15-2007, 12:32 AM
#3
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Join Date: Sep 2006
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RE: Vibration from undercarriage
ORIGINAL: pengintamer
id have to say the easiest thing to check is the u joint angle. here's some stuff i pulled up:
Snip----
Here's the web page: http://www.drivetrain.com/driveline_angle_problem.html
id have to say the easiest thing to check is the u joint angle. here's some stuff i pulled up:
Snip----
Here's the web page: http://www.drivetrain.com/driveline_angle_problem.html
Steve
05-15-2007, 02:15 AM
#5
1st Gear Member
Join Date: May 2007
Location: Rochester, NY
Posts: 82
RE: Vibration from undercarriage
when u put the gears in did u make sure to check the back lash that could cause problems. the rear end has a vibration damper so u might not feel it but it might be there.
05-15-2007, 05:52 AM
#6
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RE: Vibration from undercarriage
ORIGINAL: Topdog922
when u put the gears in did u make sure to check the back lash that could cause problems. the rear end has a vibration damper so u might not feel it but it might be there.
when u put the gears in did u make sure to check the back lash that could cause problems. the rear end has a vibration damper so u might not feel it but it might be there.
It could be the U joints I suppose. I'll look into it.
05-15-2007, 05:55 AM
#7
6th Gear Member
Join Date: Jan 2004
Location: United States
Posts: 12,575
RE: Vibration from undercarriage
I had a bent yoke, which is basically the same thing as a driveshaft being out of balance.
The car would simply vibrate harder and harder the faster you went. I didn't know wtf it was and went racing with it, was scary at 100 MPH
If the d/s was out of balance it would not come and go, and trust me you would notice it right away unless it was just barely messed up.
The car would simply vibrate harder and harder the faster you went. I didn't know wtf it was and went racing with it, was scary at 100 MPH
If the d/s was out of balance it would not come and go, and trust me you would notice it right away unless it was just barely messed up.
05-15-2007, 06:28 AM
#8
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RE: Vibration from undercarriage
ORIGINAL: 2000GT4.6
I had a bent yoke, which is basically the same thing as a driveshaft being out of balance.
The car would simply vibrate harder and harder the faster you went. I didn't know wtf it was and went racing with it, was scary at 100 MPH
If the d/s was out of balance it would not come and go, and trust me you would notice it right away unless it was just barely messed up.
I had a bent yoke, which is basically the same thing as a driveshaft being out of balance.
The car would simply vibrate harder and harder the faster you went. I didn't know wtf it was and went racing with it, was scary at 100 MPH
If the d/s was out of balance it would not come and go, and trust me you would notice it right away unless it was just barely messed up.
It'd be so nice to have a lift at my house
05-15-2007, 08:26 AM
#9
6th Gear Member
Join Date: Jan 2004
Location: United States
Posts: 12,575
RE: Vibration from undercarriage
ORIGINAL: BleedinBlue
I don't know if the noise is always there and I just can't hear it over my exhaust, or if it does come and go. It is still possible that it is the exhaust. And I don't believe it effected my driving/handling at all.
It'd be so nice to have a lift at my house
ORIGINAL: 2000GT4.6
I had a bent yoke, which is basically the same thing as a driveshaft being out of balance.
The car would simply vibrate harder and harder the faster you went. I didn't know wtf it was and went racing with it, was scary at 100 MPH
If the d/s was out of balance it would not come and go, and trust me you would notice it right away unless it was just barely messed up.
I had a bent yoke, which is basically the same thing as a driveshaft being out of balance.
The car would simply vibrate harder and harder the faster you went. I didn't know wtf it was and went racing with it, was scary at 100 MPH
If the d/s was out of balance it would not come and go, and trust me you would notice it right away unless it was just barely messed up.
It'd be so nice to have a lift at my house
Unless its just really really really just barely out of balance your going to notice it. My entire car was shaking like crazy.
05-15-2007, 08:39 AM
#10
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Join Date: Jun 2006
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RE: Vibration from undercarriage
ORIGINAL: 2000GT4.6
No joke man.
Unless its just really really really just barely out of balance your going to notice it. My entire car was shaking like crazy.
No joke man.
Unless its just really really really just barely out of balance your going to notice it. My entire car was shaking like crazy.
You are in Columbia, aren't ya? What track do you go to?