Bit of an awkward problem I’ve had with my car.
Few years ago I started to get a very slight judder on braking with discs and pads that had been fitted on the car for over a year. I replaced the discs for drilled and grooved that I’d bought off the ‘Bay and the pads were decent (champion I think) from Halfords.

Problem seemed to go away but returned a few months later. I tried replacing the brake reaction bushes (one hell of a nasty job), but the problem still remained.

Ended up taking the car to Haliwell Jones BMW and paid the diag fee. They suspected the ball joints and replaced them. This still didn’t cure the problem and they blamed the “after market discs and pads”. After a bit of a legal battle I got the money back, but it still left me with the problem.

Called a few garages including Trenics in Queensferry who suggested a replace of the discs and pads. Replaced these yesterday with Brembo discs and Mintex pads, but the problem still appears.

Sort of running out of options with it now. I’ve tried different profile tyres, but with the fronts; they have to be low otherwise the wheel will hit the sill when the steering is fully locked as the car was lowered about 12 years ago.

The only other thing I think it might be is the wheel hubs, but E36’s never suffered much with bad hubs. Pondering taking it to the lads in Trenics as I could end up replacing bits until the cows come home.

Any ideas?

Thanks.

when was the fluid last changed? how many pots are the calipers?

Changed the fluid only a couple of months ago. Completely replaced both front callipers. When I took the old pads off both sides seemed about the same thickness so I think it would be unlikely that the brakes are binding.

Seemed a bit odd that I got the judder within only 5 miles on new pads and discs.

Thanks.

is it defo judering at the front, possibilitys of it being rear?

wishbones & mounts ok? steering rack free of play, wheel bearings ok?

Put a runout gauge on the disks, then try the hubs.

I had a similar issue when I got my E61 - replaced the rear disks after a run out gauge showed they where not running true, but the problem was still there. So I then put the gauge on te hub face and there was still run out, so I replaced it, and that solved the problem. If you cant find any run out on those then it will be a bush somewhere.

It could be the rear, but I would suspect it be unlikely as I have to go over 50mph and brake to notice. In doing this, the car would load most of its weight on the front.

I've never used a run-out gauge before. Are they cheap to buy? If not, can they be loaned?

I was worried about putting the new discs on and finding the hub was out and it damaging the discs again, but I've only driven it about 15 miles since replacing the brakes so I hope they'd be ok.

Dial Test Indicator is what you need to check the discs, with base they come to around £30 for an okish one or failing that if you know any engineers who has one as to borrow it.

To check the run out take the wheel off then put the wheel nuts back on.

Use the magnetic base on the strut then place the DTI on the face of the disc and measure the run out.

If all os ok then set the DTI so it's in the clamping face of the disc and the DTI feeler on the friction part of the disc and compare if it out.

here's a link to a cheap one...

http://cgi.ebay.co.uk/Dial-Test-Ind...60449891202?pt=UK_Measuring_Tools_Levels

Thanks very much for all the advice guys. Do you reckon I leave driving it until I can test the run-out to ensure the new discs don't get damaged?

Neil.

Think I found the problem, not that you really need a dial indicator to see it. Seems that the disc retaining bolt had become stuck in the past so some garage just whizzered it off, damaging the hub in the process.

This causes the edge of the hub to be out by a very great deal. The inside of the hub is very near true.

When I rotated the wheel with the brake gear attached you could actually hear and feel the difference in friction as one side was noticably higher than the other as the disc moved through the pads.

Replacing the hub seems a logical place to start. Do you reckon a scrap yard hub would be of acceptable quality? Would it be worth dial indicating it first before purchase?

Thanks,

Neil.

Have you checked the price new, surprisingly cheap sometimes, but surprisingly dear at others

Will make some enquires tomorrow. It's always been a bit wick to get the disc aligned without the retaining screw. It may not fix the wheel wobble, but it defo looks like a good place to start.

Rear hub is just under £55 at eurocarparts.

Used hubs are £29 on fleabay.

cool thanks. I was going to call Haliwell, but they'd want $$$. I might ask my bro's mate in Neptune.

Disc retaining bolt is probably £341.47 + VAT lol.

Fleabay have a new one for £30. Might try Senars too as it's good to get local in case it needs to go back.

Realoem is good. To check your part numbers and diagrams etc:

http://www.realoem.com/bmw/showpart...443&btnr=31_0424&hg=31&fg=10

Eurocarparts is only in Chester.

Good handy site, could do with those for a few more makes (I'm deffo not a BMW person)

i could prob ring round my usual suppliers and see what they say?

i have plenty of super trade accounts

Thanks guys. I ordered one on ebay. New for £30, matched the part no on the realoem site.

Cheers.

You'll need a new floor if that comes through the letterbox

note to self dont stand by the letterbox too!

Did the job. Some lessons learnt

1) Had to borrow a massive torque wrench to undo 46mm nut and eventually tighten to 215ft/lbs
2) Don't get cheap hubs (I had to send the £30 one back). If BMW consider brands like FAG (OEM) or Febi Bilstein. The difference in quality is vast and it's your life that you need to consider.
3) Dremel type tool comes in handy to cut out the nut locking tab.
4) Replace both the 46mm nut and the dust cap (only cost a few £)

Seemed to improve the wheel wobble situation. Going to Dial Indicator the other side brake discs and hub, may replace. BMWs are quite sensitive to wheel balancing, so will prob get both fronts balanced for the small cost.