E39 530d Brake Judder / Pulsing

[gixerboy]

Evening all,

I'll try to keep this short but any advise would be gratefully received. E39 530d touring 175k 2003 Deflapped auto with working webasto !
Problem with brakes for the last 7 months or about 20,000 miles.

The easiest way to describe it is brake judder but not the usual steering wheel wobble at speed, the feeling given is a pulsing through the whole car as you pull up to stop at low speeds, even while trying to keep the same pressure on the brake pedal the car will feel like you have a warped disc and when finally coming to halt rather too abruptly all while under relatively gentle braking.

BMW replaced front discs under parts warranty (BMW mechanic mate) and agreed with me that n/s front caliper seized so drove straight home with new front discs on and changed front callipers, still got problem so now have changed front discs again incase of warping on 18 mile journey home from BMW, problem still there.

This weekend borrowed run out gauge and confirmed that no run out on front or rear discs but being a really fussy person changed rear brembo discs for genuine along with rear pads and shoes, 150 mile bedding in journey and problem still there !!! Now the little hair I had has gone !

So to recap all brake parts genuine and new or one month old apart from front pads which are 3/4 worn and were faced to new discs and new discs centered with clean hubs before fitting.
Brake fluid changed 2 months ago and no error codes stored apart from P1260 but don't get me back on that old issue.

I'm thinking trying to disable rear brakes and test drive on short journey ? Rubber components on brake lines ? Auto gearbox?
As you can tell Im getting desparate !

Thanks for reading and any advise

If in doubt ? FLAT OUT

[gixerboy]

Sorry that should be advice, oops.

[E39mad]

Have you had the control arm bushes replaced at any time?

[gixerboy]

Thanks for response.

Front control arms (brake reaction arms as I call em) and wishbones replaced earlier this year complete arms and bushes but unsure of exact make but came from GSF. Brake reaction arms could be Firstline ones which is slightly worrying as their wheel bearings fail prematurely and engine mounts too ! All replaced within 6 months of fitting for genuine !

Why do you mention control arm bushes could these be in question ?

[E39mad]

The infamous E39 wheel shimmy can be a pain as the cause could be many things and you have done most of them by replacing discs,pads or renewing sticking caliperss.

The other things are the suspension/steering bushes which you seem to have replaced however IIRC and don't quote me on this but I read on a forum somewhere that unless you use genuine parts for these items the alternatives are poor and can cause issues.

Assume also that the alignment and balance is in order?

[Chris F]

I am getting something similar on my E60, its going in for an alignment check on Tuesday.
How could bushes cause vibrations unless they were totally shot?

[gixerboy]

Thanks again for replies, got a mate over for Xmas and his 2003 525d touring needs a service and suspect if my wife can entertain him long enough I'll borrow his abs pump !

Will also look at replacing all non genuine arms / bushes upfront over next two to three weeks and any improvement I will advise outcome.

[Blingo]

Am I reading right, everything is new EXCEPT the front pads which are 3/4 worn?

I would always fit new pads with new discs, especially if there was a problem lurking. If I am reading right I would renew the front pads straight away if only to eliminate them from your enquiries.

Are your wheels standard?

[pb2301]

Just a thought - what condition are the tyres? Any uneven wear? Or maybe buckled wheels?

[gixerboy]

Thanks again for replies, wheels are standard and new front tyres 2 months ago which over the years i've found Michelins the best for mileage @ 30k per set. My tyre man has always balanced using a duo system which uses the wheel studs rather than the centre ring as he knows I'm that fussy !

[gixerboy]

Thanks again for replies, wheels are standard and new front tyres 2 months ago which over the years i've found Michelins the best for mileage @ 30k per set. My tyre man has always balanced using a duo system which uses the wheel studs rather than the centre ring as he knows I'm that fussy !

[slim_boy_fat]

Intermittant ABS module fault?

[gixerboy]

Problem solved and thanks again for all the pearls of wisdom shared.

Replaced front discs and pads, 200-300 miles of bedding in taking it very gently and no pulsing or uneven feel, at last !
Spent a long time cleaning and aligning new discs and wheels on rims and she's so smooth again. One of the new front discs seemed to be the culprit and of course that was the last one changed !

However my mate just been over with his 525d E39 2003 touring 140 k and has error P3505 and P0480 stored. Bit annoyed that I did not check before performing flapectomy as if a glow plugs down then it would have been easy to do while inlet manifold off.

Does P3505 relate to a specific Glow plug or the control box?