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Before I purchased my car, I was talking to a different seller about his car. He was a Mechanical Engineer for one of the domestic (american) oem's. I'm an ME myself and could tell he knew what he was talking about-knew how to diagnose a problem and fix it properly. He mentioned that his car had a driveshaft whine/high pitched howl at highway speeds. He looked into it and found a little known bmw recall stating that the driveshaft should have an "isolator" placed on it. From what he described (he did it himself) it's like sticking a small length of dynamat to the driveshaft (around obviously to avoid balance issues). I can't really remember, but I can see if I can contact him again to learn more. He said it completely removed the whine.

Mine has a slight whine as well, +/- 5mph around 57mph, coming from the rear center of the car, and goes away when I lift off the throttle. My guess is it's a high order resonant frequency of the shaft spinning at that specific speed which is not completely damped with the stock fittings-not necessarily a sign of a bad pinion bearing (mine only has 37k miles on it, driven gently from previous owners).
 

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Discussion Starter #22
Before I purchased my car, I was talking to a different seller about his car. He was a Mechanical Engineer for one of the domestic (american) oem's. I'm an ME myself and could tell he knew what he was talking about-knew how to diagnose a problem and fix it properly. He mentioned that his car had a driveshaft whine/high pitched howl at highway speeds. He looked into it and found a little known bmw recall stating that the driveshaft should have an "isolator" placed on it. From what he described (he did it himself) it's like sticking a small length of dynamat to the driveshaft (around obviously to avoid balance issues). I can't really remember, but I can see if I can contact him again to learn more. He said it completely removed the whine.

Mine has a slight whine as well, +/- 5mph around 57mph, coming from the rear center of the car, and goes away when I lift off the throttle. My guess is it's a high order resonant frequency of the shaft spinning at that specific speed which is not completely damped with the stock fittings-not necessarily a sign of a bad pinion bearing (mine only has 37k miles on it, driven gently from previous owners).

Thank you for your contribution to this thread. I still have the whine, which really sounds like a failing bushing or bearing. What is confounding, is that it only happens after driving about 200 kms (120 miles±), and if the car is stopped for just long enough for me to get the rear wheels jacked up into the air (5 minutes±), it's gone. I've put about 2000 km on the car since first noticing it, and it hasn't gotten any worse. My hope was that it would become less intermittant, and therefore easier to diagnose.

What differs between our situations, is that when it happens, there is no change in the noise or frequency whether or not I'm on or off the gas, neutral, or in gear, clutch in or out. I'm beginning to really think the centre support bearing is at fault, but don't really know how to check it. There is some rotational play in the driveshaft, but I can't feel any up/down movement.
 

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Discussion Starter #23
Can the exhaust be dropped with the car on stands?

My guess is propshaft center bearing and the bushing that goes into the gearbox output shaft.

Do you have spacers fitted?Becuase if the bolts in the rear are too long,they make contact with the handbrake internals and can cause funny noises....
Winner winner!!
You (and a couple of others) are correct - the centre support bearing must be what is making the noise - I was able to get the rear end up in the air and get the noise to finally show itself while the car was good and hot - it is coming from under the heat shield about 5" towards the rear from where the exhaust cross bracket is located - and that has to be the location of the support bearing.

I've read your excellent write up on the propshaft bearing replacement, but wonder if you can provide any insight regarding step 1: removal of the whole (stock) 1 piece exhaust system. Can this be done with the car on 18" jackstands (with me on my back underneath)? A mechanic removed the exhaust a year ago to change the clutch, so I'm assuming the bolts at the collectors shouldn't be rusted on that badly. Do I start at the collectors, then go to the mufflers, then do the centre exhaust support last, or best to start at the front and work my way backwards with the exhaust hanging down as I go?

Do any of the nuts/bolts for the guibo or driveshaft flange require replacement with new parts?

Many thanks!
(I'm very pleased to now know where the $%## noise is coming from!)
 

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I've read your excellent write up on the propshaft bearing replacement, but wonder if you can provide any insight regarding step 1: removal of the whole (stock) 1 piece exhaust system. Can this be done with the car on 18" jackstands (with me on my back underneath)? A mechanic removed the exhaust a year ago to change the clutch, so I'm assuming the bolts at the collectors shouldn't be rusted on that badly. Do I start at the collectors, then go to the mufflers, then do the centre exhaust support last, or best to start at the front and work my way backwards with the exhaust hanging down as I go?

Do any of the nuts/bolts for the guibo or driveshaft flange require replacement with new parts?

Many thanks!
(I'm very pleased to now know where the $%## noise is coming from!)
It can be done on jackstands, but the exhaust is a pain (and weighs a ton). Seriously, be careful and make sure that someone knows you are working on it...

If you are doing a complete driveshaft then you'll only need the three locking nuts for the bolts that connect the guibo to the transmission as well as the insulating strip referred to above (it's in the parts catalog under individual driveshaft parts and installs between the CSB and the tunnel).

If you are doing the CSB alone then note the following:

Replace the guibo and centering bushing (unless this was done with the clutch).
Replace any of the nuts that you remove from the guibo.
Carefully inspect the CV boot on the rear of the shaft for cracks... if it is, then you'll want to add this to the list.
Be very careful not to over-extend or over-compress the CV joint when you remove the shaft.

IMHO if you are replacing two major driveshaft components then it makes sense to replace the whole shaft as a complete unit or buy a reman shaft from the guy in Oregon.
 

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Discussion Starter #25
IMHO if you are replacing two major driveshaft components then it makes sense to replace the whole shaft as a complete unit or buy a reman shaft from the guy in Oregon.
That sounds like the way to go. I've asked for a quote from Driveline Service of Portland for a remanufactured assembly. I'm assuming I should source a flex disk and centering bushing.

Thanks for the heads up on the weight of the exhaust. That's why I paid someone to do my clutch...

Cheers,
Jeff
 

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Really interested in this !!

I HAVE HAD THIS VERY SAME NOISE FOR SOMETHING LIKE A YEAR wee wee wee with no noticable change in pitch or frequency with speed but definitly STOPS when you stop and is KIND of RANDOM as well .... tried the jacking up and running with the reassuspension loaded through the lowere arms but off th eground so the wheels could turn .... changed the entire rear suspension propshafts... no change and new rear bearings (needed but not the noise) had a friend listen while it was making the noise ...HE said it sounded like it was coming from the middle of the car ..... in the car it is very noticable at times but doesnt seem to alarm anyone standing by on the outside .... I never get the head snap of like "dude WHAT IS WRONG with your car "?? so it must not be that loud outside the car .. makes sense it is between the exhause heatsheilds and floor boards .....
at times I have small vibration throught the shifter .... so maybe its just the center bearing or guibo....


please keep us posted as to what you find !!.............and I thought it was JUST ME !! LOL
 

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Dont worry its just this...

<object width="480" height="385"><param name="movie" value="http://www.youtube.com/v/8F_G2zp-opg?fs=1&hl=en_US"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/8F_G2zp-opg?fs=1&hl=en_US" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="480" height="385"></embed></object>
 

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very funny .........

but seriously have you made any progress diagnosing the OUI ??
 

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Discussion Starter #29
The noise is the center driveshaft support bearing. I was finally able to reproduce it with the car rear jacked up (wheels in the air) and running in 6th gear. Noise was coming from inside the tunnel just aft of the exhaust center support. Exhaust has to come off to access, but this is absolutely where the noise was coming from. I'll look at all the driveshaft components when I have a chance to get the car up on jackstands and drop the exhaust.
 

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Awesome !! thanks !! this last weekend I think I was able to identify the same cause as the noise is louder IN the car than OUTside the car ... it also is coming from the same general area as you describe ..... MY exhause is easier to drop as when I installed the DUAL TUBI I made a break just ahead of the center support crossmember with V-Band clamps and so I can easily drop the sectoin I need to get at the drive shaft !!

thansk for your posts on this it really helped a lot to find this noise was driving me nuts :confused3
 

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Discussion Starter #31
It can be done on jackstands, but the exhaust is a pain (and weighs a ton). Seriously, be careful and make sure that someone knows you are working on it...

If you are doing a complete driveshaft then you'll only need the three locking nuts for the bolts that connect the guibo to the transmission as well as the insulating strip referred to above (it's in the parts catalog under individual driveshaft parts and installs between the CSB and the tunnel).

If you are doing the CSB alone then note the following:

Replace the guibo and centering bushing (unless this was done with the clutch).
Replace any of the nuts that you remove from the guibo.
Carefully inspect the CV boot on the rear of the shaft for cracks... if it is, then you'll want to add this to the list.
Be very careful not to over-extend or over-compress the CV joint when you remove the shaft.

IMHO if you are replacing two major driveshaft components then it makes sense to replace the whole shaft as a complete unit or buy a reman shaft from the guy in Oregon.
Hi AMP,

The Oregon guys with the remanufactured driveshafts never did get back to me (maybe because I'm in Canada?), but my wife is away for a few days, and I decided to dig in with the CSB, as I had the part and was only going to do that (with the isolator cord).

I dropped the exhaust, removed the driveshaft from the guibo (left the guibo on the car), the rear driveshaft CV nuts, etc. and now I have the CSB replaced on the driveshaft. That bolt that holds the driveshaft halves together (18mm) is a pain, and I've got it tightened as much as I could with the box end wrench that I had to grind down. Anyways, at least no problems with the alignment of the driveshaft halves.

At this point, I really don't want to do this again on my back in my garage, so I have taken your advice and ordered the new guibo and centering bushing, (along with a CV joint gasket which was in pieces), but I'm really confused about how to best put it back up once I've got the everything. I ended up taking the tranny support off so I could defeat the guibo to transmission bolt nuts, but the force I had to apply has me worried about how I could possibly put it back together without twisting the crap out of the new guibo (the old one looks perfect, by the way). I can't think of any type of wrench or socket that I could use to apply force to the nuts, while holding the bolts stationary. Taking them off required me to turn the bolts, with a wrench on the nut braced on a body support. Should I bolt the guibo to the driveshaft prior to putting it all back up? That would leave me with the 3 guibo to tranny nuts to contend with - any tricks to get torque on these would be appreciated!

Assuming the driveshaft halves are correctly realigned, and I get the diff flange mount back together as per those alignment marks, is it necessary to worry about the relationship between the driveshaft and the tranny output (given that there is a new guibo now going in)?

The last question I have is regarding the order of reassembly back on the car assuming the guibo is now mounted on the driveshaft. Transmission end first, Diff, then CSB?

Many thanks for your help!


P.S.
The old CSB rattles after removing it from the driveshaft, so that was (I HOPE!) the issue. From what I've read, this bearing should be pushed towards the front of the car when mounting - mine was as far back as the elongated holes would allow - likely the result of the clutch install by my indy shop (ex BMW Service manager).
 

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I have the EXACT same noise, constant noise in low speeds (<80km/h) with no real correlation between speed/braking/gear/clutch/etc.. Exactly as a couple of you have described it.

I leave music on all the time because it drives me nuts. I have already ruled out the wheel bearings but now I will look into the centre driveshaft bearing. I hope that's all it is!

Thanks guys!
 

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Discussion Starter #33 (Edited)
Done, fixed, IMPROVED!

I wanted to updated this thread for anyone with similar issues:

1st off, many thanks to all who've taken the time to post DIY's and information with regards to changing out a CSB (Centre Support Bearing), or other driveshaft related (guibo!) issues. Special thanks to AMP, who took the time to explain the process and do some hand holding throughout the repair. Without Andrew's help and advice, I'm sure the results just wouldn't have been as good, and some of the old parts would have remained on the car.

My problem seems to have absolutely been caused by the CSB bearing, which rattles now that it is out of the car. As per AMPS advice, I replaced the CSB bearing with the terostat (sp?) goop, guibo (and the centering sleeve/bushing), and guibo nuts. Initially, I was just going to do the CSB, but given the extent of disassembly required to get to the CSB, I didn't want to EVER have to do it again, in my garage, on my back.

It seems that the Indy shop that did my clutch probably distorted the guibo while zipping on the nuts from the bolt head end, rather than tightening the nuts with the bolt head held stationary. This in turn twists or loads the guibo, and while the old guibo looked 100% fine, the drivetrain is somehow much smoother, particularly felt in the 1-2 and 2-3 shift. The car is much easier to drive smoothly now, and whatever small amounts of vibration felt during deceleration (which was not intrusive) are gone. My car used to jerk a bit when cold while slowly driving, and that has stopped. I believe the previous guibo installation was "loaded" and the cause, as the old CSB did not drag, but was noisy.

I have a large selection of tools considering that I'm a shade tree mechanic, but found it necessary to cut and modify wrenches to get access to the 18mm bolt that holds the driveshaft halves together, as well as cut the box end of a 21mm wrench off in order to put a snipe on it to facilitate tightening the guibo nuts. A REALLY shallow 16mm socket on a low profile breaker bar (I used a flat bar with 3/8 drive on it for typically doing serpentine belts) is valuable for getting the rear driveshaft CV joint off the diff flange as well. The CV joint to diff flange required a new gasket, as the old one was in pieces in the CV joint grease. Not a big deal, if you're prepared.

I know if (heaven forbid), I need to do this job again, I'll do it in 1/3 of the time, but if you haven't done it before, I'd suggest giving yourself a few days to be safe. You don't want to put it all back together with any suspect parts, and may decide to replace more than you were going to initially - if you're lucky, the parts won't be two days away...

The job is certainly a DIY, but in my opinion, don't do the job yourself to save money (unless your time is worth nothing) - do it yourself to make sure it's done right! Don't skimp on replacing old parts that look fine while you're down there, and realize that removing the driveshaft might expose other issues you'd be foolish to ignore once you get there.

Just a couple more tips:
-Get a buddy to help (I didn't)
-Start in a clean garage (I didn't)
-Next time I do this, I'll take my rear bumper off 1st - it makes the exhaust removal easier for one person without hurting your bumper, and isn't a big deal.
-Take the transmission support off 1st to get at the guibo nuts (I didn't at first)- support the tranny with a jack. I tried to custom bend a wrench to work around the support, and ended up taking it off anyways in order to get the guibo to tranny nuts torqued back on properly.

Try to do this when your better half/kids are going to be away for a few days, (I did!) so you can take your time. Be patient!

Cheers
 

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Hey thanks for this post..I have the same problem currently, The whining noise comes at around 20mph and last up till about 60-65mph, below that its quite. I also have some vibrations while i slow down from 55-50mph give or take 3-4mph...THe noise drive me up the wall...its a constant annoying whining. I will update on my situation as well.
 

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Dont worry its just this...

<EMBED height=385 type=application/x-shockwave-flash width=480 src=http://www.youtube.com/v/8F_G2zp-opg?fs=1&hl=en_US allowfullscreen="true" allowscriptaccess="always"></EMBED>
hihahiha
 

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I just developed this same annoying sound the other day. I thought I had a window cracked open or something like that. After having my roommate crawl around my car and stick his head out of all the windows while I was driving, we pin pointed the sound to be coming from the center of the car, right below us. We figured it was driveshaft related, and you guys seem to confirm that.

The m5 is my only car right now, and I live in an apartment complex with nowhere to work on a car, or even the tools to do so (divorce is fun :sad1:), how much is it going to likely run me at a shop to have them fix this?
 

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I have been looking to diagnose this noise for over a year.
Is the attached sound file the same noise that others are hearing?
Just want to be sure that its apples to apples.
Thanks
Sorry, for some reason I can't open up the file on my Mac. In any case, a decent shop should be able to sort it out for you.
 
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