[raptor_f22]

*sigh* another day, another problem with my beloved E92. My enthusiasm is waning as my car burns a deeper hole in my pocket. It's not been a fun first 4 months with the car.

So for a while now I've had a juddering/pulsing issue when pressing the brake pedal in my car. Had one indy who said it was warped front discs c.£300 to replace plus pads.

I wasn't sure as the symptoms weren't consistent. Have another indy who says it could be the front bushes which need replacing c.£300 or the hydro bearing (is that another term for a bush? im confused)


Best way I can describe it is that:

Speed: 65 mph down to 50mph
Road surface: Smooth, flat, motorway
Brake Force: Light
Observation: Very strong juddering/pulsating feeling through steering wheel and car (could feel it through the seat) but not the brake pedal

Speed: 70 mph down to 50mph
Road surface: Smooth, flat, motorway
Brake Force: Light
Observation: Very strong juddering/pulsating feeling through steering wheel and car (could feel it through the seat) but not the brake pedal

Speed: 60 mph down to 30mph
Road surface: Smooth, downhill, motorway
Brake Force: Medium
Observation: Some juddering/pulsating feeling through steering wheel but sensation not as strong when pressing the brake harder

The juddering is also present at lower speeds but much less noticeable.
Most recently, at high speed I feel like the pulsating feeling is now constantly there but weak compared to when i press the brakes.

Car's service history shows a control arm was changed quite recently. Has anybody had this problem? What worked for you?

She's due to go to the indy to get the rear shocks replaced c.£290 and i'm expecting a total repair bill of £600 to get the above sorted at the same time but was told it's not 100% that changing the bushes will sort it out.

I'd like to avoid spending £300 on a trial and error basis to then have to change the discs too!

Any ideas what it could be? Thanks

[wallsmk2]

My immediate thought would be the other control arm may be on its way out. If it's lower fronts then will be around £60-70 ecp and half an hour to change.

[raptor_f22]

Originally Posted by wallsmk2

My immediate thought would be the other control arm may be on its way out. If it's lower fronts then will be around £60-70 ecp and half an hour to change.

Thanks! Suppose i'm not disputing what the indy says in terms of it's a bit "trial and error" because it's not the easiest issue to really nail down, would just be put my mind at ease if I knew exactly what it was.

Hopefully it will be more around that price range!

[mjn77]

I had the exact same thing on my E46, and i replaced everything......except the front hubs, which was my next step before it was written off in an accident.

[raptor_f22]

Originally Posted by mjn77

I had the exact same thing on my E46, and i replaced everything......except the front hubs, which was my next step before it was written off in an accident.

How much did it all cost you in the end? It's frustrating as I can't get the car on a ramp myself and get someone to take a look at the various parts. Just shooting in the dark at the moment.

[Aragorn30d]

Mine has similar sensation.

Brakes is the obvious choice, and mine looked a bit rough, so i replaced them. I did front and rear and it cost me about £200 in parts.

Problem still exists.

I've bought all four front control arms (M3 spec) and will be changing those next, as that seems like the most common thing after the brakes themselves. They were about £250 from rexbo.eu It pisses me off when folk replace one control arm... They're clearly all going to be worn out, as they've all done the same work.

[raptor_f22]

Originally Posted by Aragorn30d

Mine has similar sensation.

Brakes is the obvious choice, and mine looked a bit rough, so i replaced them. I did front and rear and it cost me about £200 in parts.

Problem still exists.

I've bought all four front control arms (M3 spec) and will be changing those next, as that seems like the most common thing after the brakes themselves. They were about £250 from rexbo.eu It pisses me off when folk replace one control arm... They're clearly all going to be worn out, as they've all done the same work.

Seems like i'm not the only one suffering from this. I had another look through my service history - I was wrong in my OP. It was a rear control arm which was previously replaced.

Which goes on to your point...why only one?! Now i'm concerned it could be the other rear control arm

Car is going in to have the rear shocks replaced but i'm suspicious of the front two as well. I did my own "test" the other day - basically hands on the body and pump the car up and down but wondered if there's a better of checking whether they're gone?

Starting to miss my Honda

[wallsmk2]

It's often difficult to diagnose until they start making a noticeable noise. Over many years with much older stuff, I've learnt that you need to budget for a full refresh of the rubbery stuff after 4-5 years ish if the car is a daily driver or you'll only be chasing wobbles, noises etc. Diagnoses can often cost more than replacing the parts themselves.

If you're replacing the dampers due to wear it's likely the control arm bushes are towards the end of their life anyway.

And I've never had a warped disc on anything from classic ferraris, porsches old mercs and a few bmws, so tend not to go down that route. I'm not saying it doesn't happen but I think people assume it's the easiest option but often it's the most expensive so not logical to replace first...unless they are due for replacement of course.

[raptor_f22]

Originally Posted by wallsmk2

It's often difficult to diagnose until they start making a noticeable noise. Over many years with much older stuff, I've learnt that you need to budget for a full refresh of the rubbery stuff after 4-5 years ish if the car is a daily driver or you'll only be chasing wobbles, noises etc. Diagnoses can often cost more than replacing the parts themselves.

If you're replacing the dampers due to wear it's likely the control arm bushes are towards the end of their life anyway.

Sounds sensible I suppose. Unsure how long I can carry on driving before saving up enough to do it all in one go.

And yes, that was my feeling on the discs. From all the checks I've done they seem to be fine. The indy who said it was the discs is more experienced than i'll ever be so won't know for certain until it's all taken apart

[wallsmk2]

http://www.pelicanparts.com/BMW/tech...eplacement.htm

These are the two control arms which could be causing problems (they have so many different names). The lower is the straight one, they are relatively cheap so I'd replace the whole arm. The upper control arms (thrust arms/tension struts) are more expensive and the bushing is fluid filled so sometimes leaks. You could replace the whole arms or just the bushing. If the discs have plenty of life in them and there's no noticeable wear on any of the control arms, I'd change this bushing first as it can often be the cause of vibrations, although I've only had one wear and cause a knocking sound.

[raptor_f22]

Originally Posted by wallsmk2

http://www.pelicanparts.com/BMW/tech...eplacement.htm

These are the two control arms which could be causing problems (they have so many different names). The lower is the straight one, they are relatively cheap so I'd replace the whole arm. The upper control arms (thrust arms/tension struts) are more expensive and the bushing is fluid filled so sometimes leaks. You could replace the whole arms or just the bushing. If the discs have plenty of life in them and there's no noticeable wear on any of the control arms, I'd change this bushing first as it can often be the cause of vibrations, although I've only had one wear and cause a knocking sound.

Thanks, will take a look. The bearing/bushing which is fluid filled, I assume that's the "hydro bearing" which the second indy suspected?

[wallsmk2]

i suspect so

[Aragorn30d]

if your going to do them, replace all four and use the M3 parts.

It'll make a massive improvement to how the car drives.

Bear in mind that many of these parts wear enough that they're affecting how the car drives, but are not bad enough to fail an MOT. Mine sailed thru an MOT a few weeks back, despite its vibration.

Also, NEVER just replace the bushing. The bushing is cheaper sure, but if your paying garage labour, the cost of that will outweigh the cost of just buying the new arm complete. Pressing bushes out and in is an annoying, fiddly, time consuming job. Plus, the balljoints also wear out, and cant be replaced on their own. Far better to just replace the whole arm.

https://www.rexbo.eu/search?q=JTC1427
https://www.rexbo.eu/search?q=JTC1426
https://www.rexbo.eu/search?q=JTC1424
https://www.rexbo.eu/search?q=JTC1423

70euros each, its about £220 for all four.

[raptor_f22]

Originally Posted by Aragorn30d

if your going to do them, replace all four and use the M3 parts.

It'll make a massive improvement to how the car drives.

Bear in mind that many of these parts wear enough that they're affecting how the car drives, but are not bad enough to fail an MOT. Mine sailed thru an MOT a few weeks back, despite its vibration.

Also, NEVER just replace the bushing. The bushing is cheaper sure, but if your paying garage labour, the cost of that will outweigh the cost of just buying the new arm complete. Pressing bushes out and in is an annoying, fiddly, time consuming job. Plus, the balljoints also wear out, and cant be replaced on their own. Far better to just replace the whole arm.

https://www.rexbo.eu/search?q=JTC1427
https://www.rexbo.eu/search?q=JTC1426
https://www.rexbo.eu/search?q=JTC1424
https://www.rexbo.eu/search?q=JTC1423

70euros each, its about £220 for all four.

Wow okay...not really sure where to start with it in terms of discussing with the garage (TWG Automotive). Will said he would take a look at the problem when the car goes in for the shocks, at the moment he suspects the bushes and thinks that will set me back the £250.

Don't know what they'd charge to replace all 4 control arms and if you can bring your own parts.

[mjn77]

Originally Posted by raptor_f22

How much did it all cost you in the end? It's frustrating as I can't get the car on a ramp myself and get someone to take a look at the various parts. Just shooting in the dark at the moment.

I spent hundreds mate. I had new:

Droplinks
Shocks
Top mounts
Control arms
Control arm bushes
Steering guibo
Springs
Brake discs
Calipers
Pads
Braided hoses
Brake lines

[ade146]

If its an auto I would try the discs first, a big stop and hold it on the brakes puts a pad imprint on the disc. This is actually pad material but its almost impossible to remove and over time changes the molecular structure of the disc in that spot.
The disc may track true but will vibrate under use.
My rally car is prone to it as you stop at stage end for your time with smoking brakes. I always get annoyed with a start or finish on a hill !
Ive had a few road cars do the same thing. I had to put 335 brakes on mine in the end.

Of course its only a guess as others have said vibration on the front can be almost anything. Even tyres.
If anyone is interested there are some pretty techy articles expanding on the above.

[raptor_f22]

Originally Posted by ade146

If its an auto I would try the discs first, a big stop and hold it on the brakes puts a pad imprint on the disc. This is actually pad material but its almost impossible to remove and over time changes the molecular structure of the disc in that spot.
The disc may track true but will vibrate under use.
My rally car is prone to it as you stop at stage end for your time with smoking brakes. I always get annoyed with a start or finish on a hill !
Ive had a few road cars do the same thing. I had to put 335 brakes on mine in the end.

Of course its only a guess as others have said vibration on the front can be almost anything. Even tyres.
If anyone is interested there are some pretty techy articles expanding on the above.

My bad on the late reply, busy week at work. Would definitely be interested in reading those articles. Thanks!

[peter2704]

mine has developed the vibration,the only thing i have notice when its a cold and frosty morning, to start off its greatly reduced but comes back stronger after running a while.I am thinking its bush based,the theory is rubber/hyd hardens/thickens when cold so acts more solid with less movement but as it warms starts the give more,increasing vib??

[raptor_f22]

Originally Posted by peter2704

mine has developed the vibration,the only thing i have notice when its a cold and frosty morning, to start off its greatly reduced but comes back stronger after running a while.I am thinking its bush based,the theory is rubber/hyd hardens/thickens when cold so acts more solid with less movement but as it warms starts the give more,increasing vib??

Interesting theory... let me know what you find out once you take it to the garage

I'm none the wiser at the moment. I think my bushes AND my discs are gone. The juddering definitely occurs once I press the brake pedal no matter how hard, however also noticed that once I hit 80mph or more, there's a distinct pulsing/vibration feeling through the steering wheel too when driving along.

Feel like i'm going nuts, I notice every strange noise and sensation now and it gets amplified in my head as i'm trying to work out what's wrong

[MattOz]

I had a similar thing recently with my car. Replaced front discs and pads and its gone away. It was really annoying and meant that I wasn't enjoying my car, so something had to be done.

[peter2704]

my e46 had judder when braking and inner face of disc corroded ,new disc/pads cured issue.Also on a bravo 20 hgt had vibration , it was egging of the tyres,new tyres issues solved.Like many say its the finding on the front end that can work out expensive

[peter2704]

just checked my front lower sus arms , the big rubber bush is quite soft,wondering if this is my issue? can we fit better ones M3? any part numbers? the front lower rear rod seems ok/firm