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BMW 530i Brake Shudder and Wheel Vibration After 1,000 miles on new discs and pads

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The Hunter machine can reduce the effect of an out of round tire (oops tyre) within limits.

 

If the technician runs the complete diagnostic cycle, both tyres and wheels are measured. The program embedded in the Hunter machine then calculates a swapping routine, including indexing, for each tire onto a recommended wheel. After the swapping, the tyre/wheel is balanced with weights. For instance, a tire with 1 mm out of round mounted on a wheel with 0.5 mm radial runout with the correct indexing/orientation would then wind up with 0.5 mm runout mounted on the car - a much improved result. And after weights, be very smooth on the road. But one can also imagine that one might optimize say 3 tyre/wheels and be left with a hopeless fourth pair.

 

Further, as I read the Hunter manual tires or wheels too far out of spec result in a "do not use" flag so there is a limit to the algorithm's ability to cope with tyre & wheel variation. Apparently the machine can recommend adjusted weight placement to reduce the vibration from out of round &/or variation in tyre belt stiffness - but within limits. If the tyre is too much egg shaped there is no tire weighting that will compensate as the (perfectly balanced) 50 or so lbs of tire/wheel is bounced up and down as it rolls down the road.

 

I've see reports that many shops with Hunter machines don't run the full cycle of diagnostics since they're not willing to take the extra time measuring plus dismounting and remounting tyres.  Instead they balance each, as received, and do the best possible, which is better than conventional balancers, but not best possible. So one shop might give you great results, another only OK.

 

I don't mean to dismiss the capabilities of the Hunter machine. Within the limits of physics it does a great job. The limits being how much the belt stiffness varies and how much "egg shape" there is in the tyres and wheels. I've read many reports of people extremely satisfied with the improvement versus conventional balancing. And FWIW, my neighbour manages service in a Ford dealership & Calvin tells me the machine is far and away the best he has seen after decades in the business - but only if used properly.

 

Regards

RDL

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I would like to be sure I get the issue right if that's ok - which of the below apply in your case - can you please tick them off?

a)brake shudder (pulsating force at the brake pedal) when breaking

b)steering wheel wobble when breaking

c)steering wheel wobble when driving (not breaking)

d) vibrations felt via driver's seat when driving (not breaking)

 

 

 

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I asked for my wheels to be checked at an ats near where I was staying after suffering on the journey up ( had a shudder before I changed top mounts before journey and still evident) I booked to check all 4 was told they would check fronts then told front tyre out of round. I'm not convinced they did anything or even put them on the machine (I didn't watch as answering some emails) so will go to my local chaps now home to rule that out. 

 

They didn't charge and I was under a time pressure but was happy to pay to rule its out!

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I feel i've hijacked this thread so i've apologies to the OP but hopefully my experiences will help.

 

Today I had my trusted local ATS look at the wheel balance and the fronts needed re balanceing

 

I left the rears as they are down to 3mm so have ordered new tyres (Michelin PS4 - £103.50 fitted - ATS are doing free fitting ATM so compete very well with the on line prices once you factor fitting) and these will be fitted next week.

 

So where are we  - wheel shudder much reduced though not eradicated. Next week when tyres are fitted these will go on to the front and the just balanced fronts onto the rear - we will see what happens then.

 

I have some discs and new pads in the garage to fit if no change.

 

So progress of sorts!

 

To recap i've done 30k in the car and in that time its had:

 

Front:

thrust arms

Drop links

top mounts

track rod ends

dampers

disc and pads

 

Rear:

Dics and pads

dampers

ball joints

subframe bushes.

 

Not sure there is much left i havent changed!

 

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The key is to visually check that both wheels and tyres are true  Otherwise there is not much point in balancing them. If both are a bit off turning the tyre on the rim so that they can cancel out each other's imbalance helps. 

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Hello,

I have a 530i 2001and I had exactly the same experience as yours.

On top I have completely changed everything upfront with Meyle parts. After about 4-5000K km's the dreaded shake returned to ALL its glory ... LOL

Please note that the discs were Brembo with Brembo pads, and I have rebuild all 4 calipers and renewed the brake fluid.

New tires all around also.

The solution is VERY simple. Take the front discs out and send them to someone with a milling machine that knows about brakes and tell them to true them (don't worry it just takes about a 1 or 2/1000th of a millimeter out of the discs)

My problem is gone for good. ABSOLUTELY no shaking while braking :)

 

P.S Don't forget to change brake pads upfront and do not use the ones you have now for ANY reason.

 

Regards

Theo

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As I posted upthread a month ago the greatest cause of brake judder or shimmy that comes back a while after new discs/pads have been fitted is due to...

 

***...folks don't properly clean back the hub flange prior to fitting the disc, don't take enough care not to trap any rust flakes that might be knocked off adj components while lifting the disc into position... and finally don't check that runout at the disc edge is within limits with a dial gauge or other accurate method. If there is runout then from about 500mls onwards the effects of a shimmy or judder will often be seen. Some cheap discs will have unacceptable runout new from the box but if you don't measure it you won't know until a few hundred plus miles are covered and the judder starts.***

 

You should never need to take discs off and have them skimmed not too long after fitting... but if so it's likely to the above.

 

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7 hours ago, Droverunner said:

...

 

***...folks don't properly clean back the hub flange prior to fitting the disc, don't take enough care not to trap any rust flakes that might be knocked off adj components while lifting the disc into position... and finally don't check that runout at the disc edge is within limits with a dial gauge or other accurate method.

...

 

+1 on that.

A few years ago I carefully installed a new Zimmermann rotor after wirebrushing the hub and carefully cleaning both the hub & rotor seating surfaces. I then checked runout and got 0.005". So much for Zimmermann quality I thought.

 

However when I removed the "defective" rotor I spotted a barely visible flyspeck of black something crud. After wiping it off, re-cleaning surfaces and checking runout again my dial indicator said less than 0.001". Where that black flyspec came from I have no idea. But if I hadn't checked I'd have had a brake shudder without a doubt. Now 2 years and 30k miles later my brakes are still silky smooth.

 

And BTW, it's vital to clamp the rotor to the hub firmly with at least 3 bolts to get an accurate measurement. I've checked a rotors with only the set screw installed and got over 0.010". Then disturbing nothing else other than snugging the rotor down with 3 bolts, measured less than 0.001"

 

Regards

RDL

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The OP has not come back, pity.

 

My E39 developed a shimmy. A wheel had thrown a balance weight, rebalancing the wheels and all was well.

 

I fitted OEM discs and pads after cleaning the hub to disc mating face and never had an issue. Mine had 91,000 miles when it went and it was in fine fettle. Had to re replace the crap ECP very non genuine rear anti roll bar links for genuine ones but that was it in terms of ride and handling. Buy cheap, buy twice. 

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eicher discs and pads!!!!!! you would be better off using your ladies dishwashing sponges as pads and Frey bentos tin lids as discs 

put a full set on my 530i lasted 2 weeks and were causing judder fortunately ecp took them back and swapped them for brembos, no issues with them

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