Thumping Noise

[Ferret]

My 525tds has developed an irritating thump under full throttle...

From a standing start if you use more than 50% throttle to move off you get a repeated heavy thumping noise from under the car... Once you're underway, over about 20mph you can use full throttle quite happily and it doesnt make any noise.

I've suspected the centre propshaft bearing is on its way out as the cars been making a metallic noise/vibration at speed for a while, anyone else think a failed centre bearing could cause this, as the noise appears to be coming from the centre of the car.

[632 Regal]

yep, midshaft bushing.

[Podmore]

My 525tds has developed an irritating thump under full throttle...

From a standing start if you use more than 50% throttle to move off you get a repeated heavy thumping noise from under the car... Once you're underway, over about 20mph you can use full throttle quite happily and it doesnt make any noise.

I've suspected the centre propshaft bearing is on its way out as the cars been making a metallic noise/vibration at speed for a while, anyone else think a failed centre bearing could cause this, as the noise appears to be coming from the centre of the car.

It could be the flex plate (guibo) which attaches the tailshaft to the gearbox output flange or the centre bearing. The centre bearing is supported in a rubber diaphragm which eventually will part company with the outer frame. However if it was this bit I'd expect to hear a pretty constant racket when moving. The metallic noise suggests the guibo has let go on a couple of its attachment points. Anyway, replace both asap. It's embarrassing when your tailshaft comes flailing out from under the car at 100 km/h.

[Ferret]

It could be the flex plate (guibo) which attaches the tailshaft to the gearbox output flange or the centre bearing. The centre bearing is supported in a rubber diaphragm which eventually will part company with the outer frame. However if it was this bit I'd expect to hear a pretty constant racket when moving. The metallic noise suggests the guibo has let go on a couple of its attachment points. Anyway, replace both asap. It's embarrassing when your tailshaft comes flailing out from under the car at 100 km/h.

Yeah, trouble is I've gotta drive it 250 miles to go get it fixed lol.

I thought the auto's didnt have a guibo? Or did the later 5 speed ones have it?

[Podmore]

Actually I've just had someone point out (another thread) that the autos don't have a guibo (whoever came up with that name anyway??). Not clear from your post that you have an auto. So ..... unless you ran over someone's long-haired cat which got itself wrapped around the tailshaft ... we come back to the centre bearing. Which is a DIY job, albeit a set of ramps and a trolley jack are pretty much essential. Can you get parts mail order? Try www.bmaparts.com

[Ferret]

Actually I've just had someone point out (another thread) that the autos don't have a guibo (whoever came up with that name anyway??). Not clear from your post that you have an auto. So ..... unless you ran over someone's long-haired cat which got itself wrapped around the tailshaft ... we come back to the centre bearing. Which is a DIY job, albeit a set of ramps and a trolley jack are pretty much essential. Can you get parts mail order? Try www.bmaparts.com

Hmm, interestingly the realoem and bimmerfans websites both say that there should be a guibo on autos an no guibo on manuals? Are the sites wrong or summat?

I dont think bma ship to the uk :P however I've got depots from both of these guys Euro Car Parts (http://www.eurocarparts.com) and GSF (http://www.gsfcarparts.com) within 2 miles of where I live :)

I'm going to buy a new gearbox mounting as well and have it fitted while the rest of the kit's dropped out (I was in a rocky car park at the beach last weekend and could hear it rocking around.) Chances are the shafts been thrashing around for a while and it's torn the gearbox mountings to shreds. Most things I'd tackle by myself, but I've got no ramps and my trolley jack's at my parents place.

ecp are gonna charge me USD30 for the centre bearing and USD16 for the gearbox mounting, this sound reasonable?

One of my parents used to work for the mechanic we trust - he'll not rip me off and will probably only charge an hours labour.

After that, I can change the engine mounts myself, then need to go onto sorting out the fuel pump problem. It's got the classic drawing air into the line problem.

[mattyb]

Autos do have a "guibo" or flex disc as it might also be called. It sounds exactly as Regal said. The centre bearing. noise at lower speeds then diminishes at higher speed. 250 miles to fix ? why not have a go at it yourself?

[Ferret]

Autos do have a "guibo" or flex disc as it might also be called. It sounds exactly as Regal said. The centre bearing. noise at lower speeds then diminishes at higher speed. 250 miles to fix ? why not have a go at it yourself?

Looks like I'll have to get a guibo as well lol.

[Bill R.]

guibo or flex disc. The 535 auto doesn't and the 525 m20 auto doesn't, others vary. Your TD as a european model with right hand drive 525td comes up in the ETK as having one as picturered here. The vehicle description is along the bottom




Looks like I'll have to get a guibo as well lol.

[Ferret]

guibo or flex disc. The 535 auto doesn't and the 525 m20 auto doesn't, others vary. Your TD as a european model with right hand drive 525td comes up in the ETK as having one as picturered here. The vehicle description is along the bottom

Cheers, I'll deffo get one ordered as well :)

[JerseySi]

Definately centre bearing - had exactly the same on my old E30 325iS.
Thumping/banging under load, vibrations when driving & it also developed a tendency to destroy the bolts that hold the prop to the diff! It's a bit scary when the back of the prop lets go, thats for sure!

[mattyb]

right u r there Bill. I should have clarified that answer a bit better

[Ferret]

Got a new carrier and guibo today, question is, will it need a new bearing as well?

I was expecting the carrier to come complete with bearing, but it doesnt appear to have one present!