technical Driveshaft BMW E90 320i

[Mr Krabs]

Good day,

I am looking for places where I can have my rear driveshaft checked out or even replaced completely. It makes shrieking noise when in reverse. I recently had my left rear tyre repaired at HiQ. I am not sure if damaged occurred from it. It was like 2-3 weeks ago. I don't think so. My car is also due to have its brake pads replaced. So I am not sure if this noise is due to the brake pads needing a replacement. Or that the driveshaft needs a replacement, ie. u-joint is faulty/a ball bearing or a worn brake sensor.

It makes a noise like in this video. It became worse from Friday. Friday, it was barely audible. It sounds like as in the video now.
BMW Noise

Should I go to HiQ, and have them repair it? I am in Cape Town.

Please kindly advise. It would be much appreciated.

 

[Solo Man]

I have not listened to your video but i would suggest having the brake pads replaced and hopefully the sound will be gone. Could be a worn brake pad/s on the side of the brakes that has no sensor. Usually the sensors are left front and right rear iirc.

 

[Mr Krabs]

Awesome. I think that is the best option at the moment. Thanks a lot.

 

[DarrylvanNiekerk]

That squeaking sounds like rubber on metal to me, are all of your exhaust hangers intact?
The connection points of the prop shaft are rubberised and could be rubbing on a plate that is loose?
It could also, as suggested, be your brakes that are rubbing and vibrating through the dust plates.

Sounds very odd.

 

[Mr Krabs]

That squeaking sounds like rubber on metal to me, are all of your exhaust hangers intact?
The connection points of the prop shaft are rubberised and could be rubbing on a plate that is loose?
It could also, as suggested, be your brakes that are rubbing and vibrating through the dust plates.

Sounds very odd.

All intact. I had the brake pads replaced at HiQ. The mechanics at HiQ said the noise is coming from differential/propshaft. Specifically the connection between the two. So I guess the rubbers are gone now? Or even the flex discs. I have close to 200 000km on the clock. The lady at HiQ suggests, I should replace the differential and the propshaft, which I feel seems to be quite expensive. Suggestions?

 

[DarrylvanNiekerk]

The diff is hollow (to reduce weight) but I still don't believe that sound is being induced into the prop shaft - purely my opinion.
This is not to say there isn't something wrong with the prop shaft but that sound sounds like some metal plate vibrating and resonating.
I don't see how the sound can be coming from the prop shaft because you should be able to see something catching or rubbing - it all sits above the exhaust and under aluminum heat shields.
A problematic diff usually creates a hum or a whine not a singing sound.

Maybe try jack the rear of the car up and see if the sound is recreated with the car in gear but the wheels turning in the air?

 

[Mr Krabs]

The diff is hollow (to reduce weight) but I still don't believe that sound is being induced into the prop shaft - purely my opinion.
This is not to say there isn't something wrong with the prop shaft but that sound sounds like some metal plate vibrating and resonating.
I don't see how the sound can be coming from the prop shaft because you should be able to see something catching or rubbing - it all sits above the exhaust and under aluminum heat shields.
A problematic diff usually creates a hum or a whine not a singing sound.

Maybe try jack the rear of the car up and see if the sound is recreated with the car in gear but the wheels turning in the air?

So I jacked up the car at HiQ. The lady showed me where the sound was coming from. Could it be the propshaft disc? The car only makes the sound when it goes in reverse. I attached a short video of the lady showing me where the sound was coming from. Video of BMW

Please kindly advise. Much appreciated. Thanks.

 

[DarrylvanNiekerk]

Yeah, it all seems a bit weird.

I don't see how the propshaft could make a sound other than a vibration, especially as it is only happening in reverse. In my mind the propshaft is either balanced or not and won't make a sound on it's own.

The diff could be worn and making a sound in reverse which is being induced into the propshaft which could be a trick to figure out and repair.

Did they quote on a replacement?

The sound in the first video is very different to the sound in the second one.

 

[Mr Krabs]

Just wanted to update on this. BMW got me a new propshaft, and it fixed the problem. The problem was around the center bearing, where the grease dried out, and it was causing that noise. BMW got me the new part for around R25000. HiQ, quoted me before around R45000.

 

[DarrylvanNiekerk]

I'm glad you got it sorted though that was a pricey exercise.

I guess the centre bearing was happy moving forward because that fits with its wear pattern but in reverse being dried out it created the squeak.

Learn something new every day.

 

[Solo Man]

I am sorry to hear that is what you paid at BMW. Last year about this time i took a friends X3 propshaft to a propshaft place in Parow and they replaced the whole rear universal joint and balanced the propshaft for R2300. The centre bearing is about R1k- what i paid for mine also about a year ago. The rear uj on the X3 had run dry and seized and was vibrating badly when driving. I removed and refitted the propshaft as a favour.

 

[Mr Krabs]

I am sorry to hear that is what you paid at BMW. Last year about this time i took a friends X3 propshaft to a propshaft place in Parow and they replaced the whole rear universal joint and balanced the propshaft for R2300. The centre bearing is about R1k- what i paid for mine also about a year ago. The rear uj on the X3 had run dry and seized and was vibrating badly when driving. I removed and refitted the propshaft as a favour.

So there's no longer vibrations on the car? What's the place's name for future reference? Thank you.

 

[Solo Man]

No vibrations at all. Propshaft Engineering Cape Town.