Omega Owners Forum
Chat Area => General Car Chat => Topic started by: pauls on 10 May 2019, 19:53:32
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Cant get to the bottom of this one. Any ideas would be a great help.
Story so far. When i bought the car the car had a steering wheel shake/wobble when you applied the brakes softly. If you jumped on them no problems. I had all four replaced with after market onces(disks and pads). Issue went away so i thought warped disc. All good for about 8 months then the issue started to come back. I wondered if i had a sticking caplier so i had both front caplipers rebuilt but the problem didnt go away so i replaced both front discs and pads with bmw ones. Issue went away again. That was about 6 months ago the issue is starting to come back again.Total confused. Tyres are new pirelli all round wheel perfectly balanced. I cannot reproduce this problem on demand it just seems to do it when it wants to.
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I was thinking aftermarket discs but you have genuine on there now. :-\
When I had this issue on my Omega it was the aftermarket discs which had warped in about two thousand miles. When I checked them with a DTI the run out was nowhere near as bad as I expected, but new Trade Club discs sorted it and they've been fine since. When I had the issue, if I just lightly touched the brakes prior to braking, the steering wheel twitched back and forth, but when I braked properly it was fine, almost as if the caliper had taken any slack out between the pads and disc.
Sorry I can't be of more help. :-\
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YZ250 has said exactly what I thought.
I went the after market disc route on my Senator and had the same problems a few thousand miles later but OE discs sorted it. As Alan says ..... I'm sorry but I can't be of any more help either :-\
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What year X3?
As someone who works for BMW, I might be able to get someone to shed more light on possibly options to look at next
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It's a 2004 3L petrol
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Lower arm tension bushes (going from front of subframe to knuckle) would be our next step. Check for movement with a lever bar with the wheel in normal loaded position.
Normally oil-filled.
P/n for the arms is 31.10.3.443.127 and .128.
Do not get just a bush on these as they have a habit of splitting when installing.
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I was about to say, any intermittent wheel balancing type wobble is usually suspension bushes at the front. So get in there with a pry and find which.
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I was about to say, any intermittent wheel balancing type wobble is usually suspension bushes at the front. So get in there with a pry and find which.
my suggestion for wheel wobble on ANY strut front suspension. In order:
Check the wheels are actually round, and consider getting them balanced
Inspect the suspension arm bushes
Replace them because they're oppsed.
Get your new tyres(the oppsed bushes wore out the tyres in pretty wear patterns) balanced by somebody who knows what they're doing.
In most cases, step 2 is unnecessary
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Is it only light braking? Does it do when cornering? Is it OK when going perfectly straight?
If the answer to all three questions is yes then in my case the problem turned out to be a wheel bearing. The bearing spun OK by hand but with a little side pressure it was notchy.
I had a similar problem and when through the entire front suspension, steering rack, track rods, pads, discs replacing anything that was slightly bad and the problem persisted. The upside is the front end of the car is perfect now!
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In my experience checking the suspension bushes for play for a subtle intermittent vibration is pretty difficult. Prying the joint doesn't really give a clear enough indication.
I find if you get an assistant to start the car (wheels on the ground) and wiggle the steering whilst you have eyes on a joint you can see if there is a difference between the left and right sides of the car.
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I was thinking aftermarket discs but you have genuine on there now. :-\
When I had this issue on my Omega it was the aftermarket discs which had warped in about two thousand miles. When I checked them with a DTI the run out was nowhere near as bad as I expected, but new Trade Club discs sorted it and they've been fine since. When I had the issue, if I just lightly touched the brakes prior to braking, the steering wheel twitched back and forth, but when I braked properly it was fine, almost as if the caliper had taken any slack out between the pads and disc.
Sorry I can't be of more help. :-\
When I had the problem on my first Omega I had vibration at motorway speed (eg 80) even without touching the brakes.
I reckon the problem is as much to do with uneven wear as it is to do with actual warping. My thinking being that poor quality pattern disks are not homogeneous and that they have soft patched which wear quicker. You might measure some run-out but you will probably also find that the disk is thinner in places and hence out of balance.
Couple the imbalance and the pulsing due variable thickness with some part worn bushes and you get some properly unpleasant shaking through the front suspension and steering :(
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Not sure of the set up on an x3.
Hub flange once got bent by an over enthusiastic wheel bearing replacement.
When the discs were changed later, it gave the same result no matter how many discs went on. Just a thought.
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All responses appriecated but still cant figure out why it goes away when I replace the brakes. Surely if a Bush or wheel bearing it would be there all the time.
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Caliper pins or some old fluid in the caliper?
Does it have floating pads on the X3?
Might be something that only becomes apparent once the brakes become worn :-\
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In the case of the slightly distorted flange which the discs sit on, it takes a couple of warm ups before the problem affects the trueness of the new discs.