E30 steering wheel shake

[pommy 33]

Hopefully somebody can help!!

My steering wheels shakes (more at high speed) when I apply my brakes...

I have replaced my wheel bearing

I have upgraded all my brakes new rotors,pads & s/s braided hoses.

new wheels & balanced.

now I'm confused, as to what else it can be?

cheers.

[qwertyk1d 12]

Any previous chassis damage that you know of?

[RipJaws 3]

Check your reinforced rubber steering bushing. I had my one recently replaced and before I did I had a steering shake or wobble at high speed. Now its really nice and tight.

[dubman 39]

could be "warped brakes"

[qwertyk1d 12]

could be "warped brakes"

He's essentially changed his entire brake assembly with new bits. Don't think it would be that.

[aja540i 1906]

He's essentially changed his entire brake assembly with new bits. Don't think it would be that.

Unlikely, but not impossible! I had the exact same thing on my vr4 a few years ago, brand new discs and pads (ebc) the rotors warped in less than 200km!! It was a shitty casting and as soon as they got warm they warped, i had them machined and they did it again so i binned them within 500km!!

[humguy 9]

You say "new wheels and tyres" Check that you have the correct fit from the mag to to hub.BMW are hub centric in that they use the bearing hub to centralize the wheel not the 4 bolts. After market wheels some times need a ring to make up the difference in size and from my past experience if the ring is not the exact size then wheel wooble you will get.Plastic rings are useless. You need alloy or steel.

[yng_750 247]

Depending on what system you have my exeriances may help. Ive had an e34 shake under brakes due to a worn steering box. This also gave some slop in steering. I believe they can be tightened.

Have also had thrust arms in the e38 and e39 cause the same thing. Basically under brakes the wheel moves back enough to give either zero castor or negative castor. Castor keeps the wheels centered so no or megative allpws wheels to start skirting around. This was more evident under heavy braking. A quick stab of brakes at 60kph resulted in a thunk souns as the arms shot back and took up the slack of soft rubber.

Other test is brake hard to a stop in front of a friend. Only from 30kph or so. Come to a stop and hold the brakes on hard. Pull handbrake then release brakes. See if front wheel jumps forward. My e38 wheels would jump forward about 35mm which is alot

[Etwenty1 45]

e30's have a rack not a box. What about your rack ends and ball joints?

I had the same issue but it was solved by swapping out the rotors, calipers and pads from a donor

[pommy 33]

You say "new wheels and tyres" Check that you have the correct fit from the mag to to hub.BMW are hub centric in that they use the bearing hub to centralize the wheel not the 4 bolts. After market wheels some times need a ring to make up the difference in size and from my past experience if the ring is not the exact size then wheel wooble you will get.Plastic rings are useless. You need alloy or steel.

thanks for your input, I am running the plastic locator ring & being after market wheels I have to run a very thin spacer upfront! Otherwise the wheel nuts hit the strut....

[pommy 33]

Check your reinforced rubber steering bushing. I had my one recently replaced and before I did I had a steering shake or wobble at high speed. Now its really nice and tight.

I will check this cheers.

[B.M.W Ltd 950]

"I am running the plastic locator ring & being after market wheels I have to run a very thin spacer upfront! Otherwise the wheel nuts hit the strut...."

I would suspect your problem lies here Chris if the brake rotors are hubcentric and are running true, alot of cheap aftermarket ones don't. What brand are the rotors ?

[pommy 33]

I'm not sure!! I purchased them from NZAD in Henderson. I would be pissed off if I have to replace the rotors it's a lot of messing about... Is there a way of finding out if they are warped? I suppose I would have to get them machined! Not sure if you can do this on slotted rotors?

[aja540i 1906]

You can test if they are warped with a dial indicator, or take them to a good brake place and get them machined anyway. If they are new you should be able to machine them once without making them too thin, but it may only fix them temporarily. When it happened to me it was a piss poor casting that had significantly different material thickness from one side of the casting to the other so when they heated up, they expanded unevenly and warped. Im not talking super hot either, i was driving up North towing an empty trailer at normal speeds! Good luck!!

[B.M.W Ltd 950]

The plastic hubcentric ring will not align the wheel properly with the spacer in there as well. Try taking those off, put standard wheels on and road test again. If the shudder goes away you need to look at doing something with your spacer / hubcentric ring and or wheel choice set up

If nothing changes you need to look at steering / suspension

Edited May 17, 2014 by B.M.W Ltd

[Allanw 1071]

If it's an actual spacer, it needs to be hubcentric anyway - for the cert you need to get for them.

If it's an "adapter" one of the spacers you bolt on, then bolt the wheel on with another set of studs/bolts, it doesn't have to be hubcentric.

Both require a cert though: http://lowvolumevehicle.co.nz/2012/02/wheel-spacers-faqs/

[aja540i 1906]

The way i read the op, it is only shaking when the brakes are applied. If it was hub rings or wheels etc it would shake all the time, getting worse as speed increased. If its fine when the brakes are 'off' then it stands to reason the problem is with the brakes. I would go back to the supplier and try to swap them.

[pommy 33]

Cheers for you help guys. I have had the wheels re balanced they wasnt out by much! So I agree next step is to contact NZAD which I see is a sponsor on here.... it does only happpen when I apply my brakes & I have only done 800klms on them!

I will keep you posted.

cheers.

[sonic_attack 89]

Did you notice any scaling or rust on the hubs when you installed new rotors? Did you get the wire brush onto the hub prior to installing rotors? If they're out the tiniest twack because the surfaces aren't even it won't be helpful.

I recently, actually yesterday installed new rotors/pads all round on my e34, soursed from NZAD. I questioned the quality because of the price but don't have the issue you have, well I do but it's the hubcentric rings causing my wobble at 90KPH. More noticeable on braking too, but that problem existed prior to new rotors.

The dial indicator suggestion is a good one, that way you'll confirm sketchy rotors at least, then be able to hit up Darren? from NZAD. He seems a reasonable guy, I think being armed with and sure of the problem would be a better approach. You have a lot of "new" going on to isolate the problem - If the wheels/tyres have been balanced you could safely scratch that as a possibility, the mating of the rim to hub with the spacers/hubcentric spigot rings would be worth another look too.

The front end of these cars seem to take a lot of having everything right so it works properly. Which is probably a good thing because you're forced to acknowledge and remedy it .

[Eagle 1662]

Ive used NZAD rotors for awhile now and never had an issue, that includes plenty of track days also.

Edited May 18, 2014 by Eagle

[pommy 33]

Cheers Rod.

I can tell you I had the whole hub stripped cleaned & copper greased! I replaced the wheel bearings just incase.... then new rotors sand blasted and painted my calipers & installed braided lines!

My next step is to try the indicator test & put my old wheels back on without spaces, just incase. ( sounds daft, but could i try my old 16" wheels at the front just to test it with my 15" on the back)?

Cheers.

[sonic_attack 89]

I would. You just want to try eliminate all the possibilities. If there's no shake with OG wheels sans spacers/hub rings you're ticking a few boxes off.