E39 vibration.

No noise, just a low frequency vibration through the body..
Noticed it a few days ago at about 70mph. Now noticeable at 50-60mph.
Would I be correct in assuming it could indicate the guibo or rubber u/j on
the propshaft is failing? Cars done about 170k.
TIA.
Mike.

Maybe the wheels need balancing. Fronts are easy to tell because of the
steering vibration, but rears you usually feel through the seat base.

Wheel bearing?

It's hard to diagnose noises without driving the vehicle.


"Mike G" > wrote in message
...
> No noise, just a low frequency vibration through the body..
> Noticed it a few days ago at about 70mph. Now noticeable at 50-60mph.
> Would I be correct in assuming it could indicate the guibo or rubber u/j
> on the propshaft is failing? Cars done about 170k.
> TIA.
> Mike.

Could be Wheel balancing or Rotors.

Does he happen more when brakeing?

-Branden


"Leroy" > wrote in message
...
> Maybe the wheels need balancing. Fronts are easy to tell because of the
> steering vibration, but rears you usually feel through the seat base.
>
> Wheel bearing?
>
> It's hard to diagnose noises without driving the vehicle.
>
>
> "Mike G" > wrote in message
> ...
>> No noise, just a low frequency vibration through the body..
>> Noticed it a few days ago at about 70mph. Now noticeable at 50-60mph.
>> Would I be correct in assuming it could indicate the guibo or rubber u/j
>> on the propshaft is failing? Cars done about 170k.
>> TIA.
>> Mike.
>
>

"Branden Nelsen" > wrote in message
...
> Could be Wheel balancing or Rotors.

I'm sure it's not either of those.
Definitely feels more like something in the transmission, rather than
anything to do with the wheels or discs.
Although it's quite noticeable to me as the driver, I doubt a passenger
would notice it.

> Does he happen more when brakeing?

No. The vibration seems to be independant of brakes or throttle setting.
That's what leads me to believe the propshaft being out of balance is the
culprit.
I can get underneath it at the weekend, and check it. Just wondered if my
suspicion was correct.
Had a u/j fail on a car many years ago. It feels very similar.
Out of interest, what are the symptons of a failing Guibo?
Mike.

"Mike G" > wrote
> No noise, just a low frequency vibration through the body..
> Noticed it a few days ago at about 70mph. Now noticeable at 50-60mph.
> Would I be correct in assuming it could indicate the guibo or rubber u/j
> on the propshaft is failing? Cars done about 170k.

The others have suggested some things.
Have you carefully inspected the tires to ensure you don't have a
tread separation - especially on the rears since it seems to be
associated with the driveline?

FloydR

In article >,
Mike G > wrote:
>No noise, just a low frequency vibration through the body..
>Noticed it a few days ago at about 70mph. Now noticeable at 50-60mph.

it could be a lot of things, mostly tires, but if it's smooth
as glass at lower speeds and sersiously lumpy around 60 then
yeah, I'd think it was the rubber flex coupling.


--
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"Floyd Rogers" > wrote in message
...
> "Mike G" > wrote
>> No noise, just a low frequency vibration through the body..
>> Noticed it a few days ago at about 70mph. Now noticeable at 50-60mph.
>> Would I be correct in assuming it could indicate the guibo or rubber u/j
>> on the propshaft is failing? Cars done about 170k.
>
> The others have suggested some things.
> Have you carefully inspected the tires to ensure you don't have a
> tread separation - especially on the rears since it seems to be
> associated with the driveline?

All good suggestions, but I'm certain that it's a mechanical fault rather
than one caused by unbalanced or damaged wheels tyres or rotors. The tyres
all round are nearly new ContiSport Contacts, on near perfect BMW wheels.
I'll have a crawl around underneath at the weekend. Check the drive train
etc.
Mike.

"Richard Sexton" > wrote in message
...
> In article >,
> Mike G > wrote:
>>No noise, just a low frequency vibration through the body..
>>Noticed it a few days ago at about 70mph. Now noticeable at 50-60mph.
>
> it could be a lot of things, mostly tires, but if it's smooth
> as glass at lower speeds and sersiously lumpy around 60 then
> yeah, I'd think it was the rubber flex coupling.

I'm sure you're right. I'm 99.9% it's not tyres.
As I said though. I should know at the weekend when I check the drive train.
Mike.

On Wed, 25 Oct 2006 21:32:03 +0100, "Mike G" >
wrote:
>>
>> The others have suggested some things.
>> Have you carefully inspected the tires to ensure you don't have a
>> tread separation - especially on the rears since it seems to be
>> associated with the driveline?
>
>All good suggestions, but I'm certain that it's a mechanical fault rather
>than one caused by unbalanced or damaged wheels tyres or rotors. The tyres
>all round are nearly new ContiSport Contacts, on near perfect BMW wheels.
>I'll have a crawl around underneath at the weekend. Check the drive train
>etc.

So long as you're 100% absolutely certain that there's no possibility
at all that a wheel balance weight has come off without you knowing,
or that one of your new tyres has developed a defect, or that one of
the wheels or tyres was knocked while you weren't looking, then by all
means go ahead and dismantle the drivetrain to see if it's damaged.
If the drive train's OK, then the next step will be to take it to a
really good body shop to make sure that the frame isn't bent. If all
that checks out OK, then maybe you should look at the wheels and
tyres, and maybe the brake rotors. Let us know what happens.

Have you ever heard of Occam's razor?
--
Dan.

"Dean Dark" > wrote in message
...
> On Wed, 25 Oct 2006 21:32:03 +0100, "Mike G" >
> wrote:
>>>
>>> The others have suggested some things.
>>> Have you carefully inspected the tires to ensure you don't have a
>>> tread separation - especially on the rears since it seems to be
>>> associated with the driveline?
>>
>>All good suggestions, but I'm certain that it's a mechanical fault rather
>>than one caused by unbalanced or damaged wheels tyres or rotors. The tyres
>>all round are nearly new ContiSport Contacts, on near perfect BMW wheels.
>>I'll have a crawl around underneath at the weekend. Check the drive train
>>etc.
>
> So long as you're 100% absolutely certain that there's no possibility
> at all that a wheel balance weight has come off without you knowing,
> or that one of your new tyres has developed a defect, or that one of
> the wheels or tyres was knocked while you weren't looking,

I should have added that the vibration feels like the wrong frequency for it
to be wheel balance problem. Much higher than the wheel rotation speed.
Nearer propshaft rotation speed IMO, which is why I think the propshaft
might be out of balance, due to a failing Guibo or u/j.

then by all
> means go ahead and dismantle the drivetrain to see if it's damaged.
> If the drive train's OK,

I don't intend to strip anything down at the weekend. If the Guibo, or
centre u/j is failing it should be evident from a visual inspection.

then the next step will be to take it to a
> really good body shop to make sure that the frame isn't bent.

It's nothing to do with the body. It's definitely a balance problem.
I'm not that familiar with the E39 yet, I've only had it a couple og months,
but I do know what a failing u/j on a propshaft feels like, and this feels
very similar, but the E39 propshaft is an odd combination of flexible 'u/j',
or Guibo, Hardy Spicer type u/j and a CV joint, so theoretically it could be
any one of them. Or it could be something as simple as a balance weight
falling off the propshaft itself.

If all
> that checks out OK, then maybe you should look at the wheels and
> tyres, and maybe the brake rotors. Let us know what happens.

I'll do that.

> Have you ever heard of Occam's razor?

Yes, which is why I'm looking at the most likely, and a fairly easy place
first.:-)
Mike.