TJ Vibration: rear axle bent?
 

OK - I may have finally found the culprit.

I pulled the rear passenger axle (the vibration always felt like it was
coming from the passenger side). First off, the bearing wasn't pushed
up against the hub like it was on the driver's side -- it has a good
3/4" to slide back and forth on -- that would probably explain the
weird side-to-side shake I feel every now and then.

More importantly, when I held a straight edge up to it, there is about
a 1mm bend in the center of the axle. When I hold it on the opposite
side, I have a 1mm gap at the top and bottom of the axle.

Could a 1mm bend in the rear axle cause violent shaking? Is that big
enough to be the problem I've been hunting down for the past six months?

Re: TJ Vibration: rear axle bent?
 

It isn't 1 mm at the edge of the tire.... remember the calculations for
leverage from physics class and since the wheel is rotating we have to
factor in constantly changing vectors of acceleration.....


"Justin M" <xtexatl@gmail.com> wrote in message
news:1163276739.067460.155360@h54g2000cwb.googlegr oups.com...
> OK - I may have finally found the culprit.
>
> I pulled the rear passenger axle (the vibration always felt like it was
> coming from the passenger side). First off, the bearing wasn't pushed
> up against the hub like it was on the driver's side -- it has a good
> 3/4" to slide back and forth on -- that would probably explain the
> weird side-to-side shake I feel every now and then.
>
> More importantly, when I held a straight edge up to it, there is about
> a 1mm bend in the center of the axle. When I hold it on the opposite
> side, I have a 1mm gap at the top and bottom of the axle.
>
> Could a 1mm bend in the rear axle cause violent shaking? Is that big
> enough to be the problem I've been hunting down for the past six months?
>

Re: TJ Vibration: rear axle bent?
 

It isn't 1 mm at the edge of the tire.... remember the calculations for
leverage from physics class and since the wheel is rotating we have to
factor in constantly changing vectors of acceleration.....


"Justin M" <xtexatl@gmail.com> wrote in message
news:1163276739.067460.155360@h54g2000cwb.googlegr oups.com...
> OK - I may have finally found the culprit.
>
> I pulled the rear passenger axle (the vibration always felt like it was
> coming from the passenger side). First off, the bearing wasn't pushed
> up against the hub like it was on the driver's side -- it has a good
> 3/4" to slide back and forth on -- that would probably explain the
> weird side-to-side shake I feel every now and then.
>
> More importantly, when I held a straight edge up to it, there is about
> a 1mm bend in the center of the axle. When I hold it on the opposite
> side, I have a 1mm gap at the top and bottom of the axle.
>
> Could a 1mm bend in the rear axle cause violent shaking? Is that big
> enough to be the problem I've been hunting down for the past six months?
>

Re: TJ Vibration: rear axle bent?
 

It isn't 1 mm at the edge of the tire.... remember the calculations for
leverage from physics class and since the wheel is rotating we have to
factor in constantly changing vectors of acceleration.....


"Justin M" <xtexatl@gmail.com> wrote in message
news:1163276739.067460.155360@h54g2000cwb.googlegr oups.com...
> OK - I may have finally found the culprit.
>
> I pulled the rear passenger axle (the vibration always felt like it was
> coming from the passenger side). First off, the bearing wasn't pushed
> up against the hub like it was on the driver's side -- it has a good
> 3/4" to slide back and forth on -- that would probably explain the
> weird side-to-side shake I feel every now and then.
>
> More importantly, when I held a straight edge up to it, there is about
> a 1mm bend in the center of the axle. When I hold it on the opposite
> side, I have a 1mm gap at the top and bottom of the axle.
>
> Could a 1mm bend in the rear axle cause violent shaking? Is that big
> enough to be the problem I've been hunting down for the past six months?
>

Re: TJ Vibration: rear axle bent?
 

Justin M wrote:
> OK - I may have finally found the culprit.
>
> I pulled the rear passenger axle (the vibration always felt like it was
> coming from the passenger side). First off, the bearing wasn't pushed
> up against the hub like it was on the driver's side -- it has a good
> 3/4" to slide back and forth on -- that would probably explain the
> weird side-to-side shake I feel every now and then.
>
> More importantly, when I held a straight edge up to it, there is about
> a 1mm bend in the center of the axle. When I hold it on the opposite
> side, I have a 1mm gap at the top and bottom of the axle.
>
> Could a 1mm bend in the rear axle cause violent shaking? Is that big
> enough to be the problem I've been hunting down for the past six months?

Hell yes. Same effect as a bent wheel, depending on where the bend is
along the shaft. The closer to the hub, the worse it will be. If you
hadn't gotten it apart yet, having a buddy drive alongside looking for
the wobble would probably have given it away. If it's that much of a
gap, you should see it if you slide the axle back in, mount a wheel and
spin.

Re: TJ Vibration: rear axle bent?
 

Justin M wrote:
> OK - I may have finally found the culprit.
>
> I pulled the rear passenger axle (the vibration always felt like it was
> coming from the passenger side). First off, the bearing wasn't pushed
> up against the hub like it was on the driver's side -- it has a good
> 3/4" to slide back and forth on -- that would probably explain the
> weird side-to-side shake I feel every now and then.
>
> More importantly, when I held a straight edge up to it, there is about
> a 1mm bend in the center of the axle. When I hold it on the opposite
> side, I have a 1mm gap at the top and bottom of the axle.
>
> Could a 1mm bend in the rear axle cause violent shaking? Is that big
> enough to be the problem I've been hunting down for the past six months?

Hell yes. Same effect as a bent wheel, depending on where the bend is
along the shaft. The closer to the hub, the worse it will be. If you
hadn't gotten it apart yet, having a buddy drive alongside looking for
the wobble would probably have given it away. If it's that much of a
gap, you should see it if you slide the axle back in, mount a wheel and
spin.

Re: TJ Vibration: rear axle bent?
 

Justin M wrote:
> OK - I may have finally found the culprit.
>
> I pulled the rear passenger axle (the vibration always felt like it was
> coming from the passenger side). First off, the bearing wasn't pushed
> up against the hub like it was on the driver's side -- it has a good
> 3/4" to slide back and forth on -- that would probably explain the
> weird side-to-side shake I feel every now and then.
>
> More importantly, when I held a straight edge up to it, there is about
> a 1mm bend in the center of the axle. When I hold it on the opposite
> side, I have a 1mm gap at the top and bottom of the axle.
>
> Could a 1mm bend in the rear axle cause violent shaking? Is that big
> enough to be the problem I've been hunting down for the past six months?

Hell yes. Same effect as a bent wheel, depending on where the bend is
along the shaft. The closer to the hub, the worse it will be. If you
hadn't gotten it apart yet, having a buddy drive alongside looking for
the wobble would probably have given it away. If it's that much of a
gap, you should see it if you slide the axle back in, mount a wheel and
spin.

Re: TJ Vibration: rear axle bent?
 

Wow.... That's a lot of work to find a bent axle...

That should show up in the wheel if you jack it up and spin it, more
than enough to vibrate.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)

Justin M wrote:
>
> OK - I may have finally found the culprit.
>
> I pulled the rear passenger axle (the vibration always felt like it was
> coming from the passenger side). First off, the bearing wasn't pushed
> up against the hub like it was on the driver's side -- it has a good
> 3/4" to slide back and forth on -- that would probably explain the
> weird side-to-side shake I feel every now and then.
>
> More importantly, when I held a straight edge up to it, there is about
> a 1mm bend in the center of the axle. When I hold it on the opposite
> side, I have a 1mm gap at the top and bottom of the axle.
>
> Could a 1mm bend in the rear axle cause violent shaking? Is that big
> enough to be the problem I've been hunting down for the past six months?

Re: TJ Vibration: rear axle bent?
 

Wow.... That's a lot of work to find a bent axle...

That should show up in the wheel if you jack it up and spin it, more
than enough to vibrate.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)

Justin M wrote:
>
> OK - I may have finally found the culprit.
>
> I pulled the rear passenger axle (the vibration always felt like it was
> coming from the passenger side). First off, the bearing wasn't pushed
> up against the hub like it was on the driver's side -- it has a good
> 3/4" to slide back and forth on -- that would probably explain the
> weird side-to-side shake I feel every now and then.
>
> More importantly, when I held a straight edge up to it, there is about
> a 1mm bend in the center of the axle. When I hold it on the opposite
> side, I have a 1mm gap at the top and bottom of the axle.
>
> Could a 1mm bend in the rear axle cause violent shaking? Is that big
> enough to be the problem I've been hunting down for the past six months?

Re: TJ Vibration: rear axle bent?
 

Wow.... That's a lot of work to find a bent axle...

That should show up in the wheel if you jack it up and spin it, more
than enough to vibrate.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)

Justin M wrote:
>
> OK - I may have finally found the culprit.
>
> I pulled the rear passenger axle (the vibration always felt like it was
> coming from the passenger side). First off, the bearing wasn't pushed
> up against the hub like it was on the driver's side -- it has a good
> 3/4" to slide back and forth on -- that would probably explain the
> weird side-to-side shake I feel every now and then.
>
> More importantly, when I held a straight edge up to it, there is about
> a 1mm bend in the center of the axle. When I hold it on the opposite
> side, I have a 1mm gap at the top and bottom of the axle.
>
> Could a 1mm bend in the rear axle cause violent shaking? Is that big
> enough to be the problem I've been hunting down for the past six months?