BMW E39 5series brake judder - yorkie123
When travelling at speed, mainly above 50 mph, and If I brake quite heavily, I get a LOT of wobble in the steering wheel. I've only had the car one month, and didn't notice this until I was on the M1 and had to brake from speed because of a queue of cars ahead. It's not minor judder, it's very pronounced and before I go in to the dealer, I'd like to know what others think may be the cause. I'd like to go in there armed with some knowledge to avoid being ripped off. Thanks.
BMW E39 5series brake judder - Dalglish
like to go in there armed with some knowledge

>>

all the knowledge and more. everything you ever wanted to know but were afraid to google.

just google "brake judder".

BMW E39 5series brake judder - yorkiebar
Not googled it but its likely to be either (not in any order of likelihood)

Brakes (discs warped, calipers sticking, pads moving)

Wheel bearings

Suspension joints / bushes.

Steering components/joints

Wheels/tyres (buckled, out of balance, worn unevenly)

there are more possibilities but these are the most likely.

BMW E39 5series brake judder - yorkie123
Yorkiebar and others, Thanks for your suggestions.
It's a 530i, done just 31,000 miles, been serviced at Cooper Wimbledon.
Tyres are all Continental, plenty of tread, so I think they're not the cause.
There is some rumbling noise, at low speeds, especially around 20 mph, related to road speed. By that I mean I can hear it when I free-wheel, it's not related to engine speed, and I can feel it slightly through the steering wheel.
Can you tell me, what's the test for wheel bearings trouble? Is it just listening for noise, or is there some other way of knowing?
BMW E39 5series brake judder - yorkiebar
The test is easy but is difficult to explain in sufficient detail to make it easy but will try.

When showing/explaining wheel bearing troubles to people I always show them so they can feel it etc; by far easier than trying to explain how to do it.

Jack up the car so the wheel is clear of the ground.

Firstly spin the wheel and listen for noises.

Then hold the wheel at opposite points i.e. 6 o clock and twelve o clock and rock the wheel bewtween these points and feel for movement/play/roughness.

Then repeat at 3 and 9 o clock and then spin wheel to a different place and do it again.

Now compare wheel to either a know good one or another wheel.

Then advise what you can from there; but not all of what you might feel may be wheel bearing play which is why you need to note what play you get from where etc and noises.

If not conversant with diy like this then it be far easier to nip into a trusted garage and ask for their opinion. They are likely to test it for free and be bit more accurate in their diagnosis for you.

hope this helps
BMW E39 5series brake judder - Dalglish
and before you start spending dosh at gsf or otehr places on suspension components, check your wheels are tighened to the correct torque for e39.

i am not an expert, but i am led to believe that these should be 120nm ( or about 89 ft.lb in old money )

BMW E39 5series brake judder - Aprilia
These cars can suffer with premature wear to the front suspension components (wishbones-balljoints) anything from 60k miles up is suspect. This often manifests itself as brake judder or a slightly 'skittish' feel when one wheel goes over a road imperfection like a manhole cover - the car will 'wriggle' slightly. A very thorough examination of the front suspension (using a pry-bar to load the components) is the best way forward. You'll probably find that your local ECP or GSF factors has the parts in stock - they are fairly fast moving.
Also do the obvious and check out the condition of the brake discs and pads (front AND rear). Quality aftermarket discs and pads are not too dear for these cars so if there is any noticable deterioration (grooving, warping, edge corrosion beyond about 5mm) then its worth repalcing with new parts.
BMW E39 5series brake judder - Aprilia
With just 31k I would expect the suspension to be in good condition - although it is possible someone's hit a kerb and bent something. Always pays to put it on a ramp and do a quick visual inspection of suspension and brakes.

I doubt a bad wheel bearing would give brake judder - it would have to be really really worn to do that. To check for a duff wheel bearing nowadays I use my infra-red temperature meter. After driving the car around for a bit take the temp of both front wheels at their centre (where the bearing is) - if there is a significant discrepancy and one is unusually hot then there is problem (bearing, or possibly binding brake). These are handy little gadgets and you can get them for less than £20 now.
BMW E39 5series brake judder - yorkiebar
Ok, good useful tool but not everybody is going to want one!

I think we are just trying to ascertain if it is wheel bearing or not just yet though.

Agree about good visual inspection, but not sure if Op is diy type yet either,.

Not meant offensively or rude btw