Shaking from Front of B!0

ollieebmw · Post by **ollieebmw** » Wed Sep 12, 2012 11:37 pm

Greetings.
Yea seen a lot of articles about replacing the whole thrust bar but my problem only happens with braking. If this works then i may end up doing all the the other suspension rubbers over a period of time. My disc apparently were tested to see if they were warped and they are. I am going to keep the disc and get them checked elsewhere. Should be picking car up tomorrow so will see what happens and report back. thanks for the info though, much appreciated.

jamesa · Post by **jamesa** » Thu Sep 13, 2012 9:43 am

Keep the feedback coming

Whilst on the E39 section of `said forum` I noted a brake bedding in process from STOPTECH ... yet more associated info !

greenelekta · Post by **greenelekta** » Thu Sep 13, 2012 10:43 am

jamesa wrote:Just joined BIMMERFORUMS and found this ... http://forums.bimmerforums.com/forum/sh ... p?t=884627

I used the same link from Bimmerforums as jamesa mentioned for reference when I replaced both my thrust arms on my b10 Touring.
I got Lemforder items from Eurocarparts and it took me about 2 hours a side, ball joints took some moving!

ollieebmw · Post by **ollieebmw** » Thu Sep 27, 2012 3:04 pm

Greetings...

Well I have finally changed the thrust arm bushes but also changed the front disc back to OEM along with new brake pads. All the problems are solved. No more shuddering when braking. Loads of brake dust compared to the back. I am going to take EBC disc to have them checked out again to confirm whether they are warped. Still got EBC disc on the rears with red stuff pads which are supposed to be warped as well but cannot feel any shuddering when baking. Will update again soon.....

ade and liz flint · Post by **ade and liz flint** » Thu Sep 27, 2012 4:03 pm

Good news

Warped rear discs (if indeed they are) will have much less effect than warped fronts as the overall setup at the rear is far less sensitive as it is a much stiffer suspension and bush arrangement than the front. Issues at the rear only become apparent if your rear bushes start to come apart.

You may find refitting your EBC discs to the front with minor warp will be acceptable now as your suspension arms will be much stiffer and less sensitive to the vibration and thus not allow the response levels you saw before. However, you may still get a little steering wobble if they are badly warped. Quick swap-out though, so maybe worth a try.

ollieebmw · Post by **ollieebmw** » Thu Sep 27, 2012 4:22 pm

Greetings..

Yeah I'm thinking of just swapping them to see but will get them checked to make sure they are not badly warped first. Not sure whether I should have different set up on front and rears though so still may change rear disc when finance allows....
silly question...How do you include the text from another person in your reply. I thought it was copy and paste text but doesn't come up in a box when I do it?

ade and liz flint · Post by **ade and liz flint** » Thu Sep 27, 2012 4:27 pm

ollieebmw wrote:Yeah I'm thinking of just swapping them to see but will get them checked to make sure they are not badly warped first. Not sure whether I should have different set up on front and rears though so still may change rear disc when finance allows....
silly question...How do you include the text from another person in your reply. I thought it was copy and paste text but doesn't come up in a box when I do it?

I would avoid a different setup as the friction will be different front-rear so will afffect the balance under severe braking.

To include someone else's diatribe in your reasoned response

, click on 'quote' box on the posting you wish to quote and it will open a new reply for you with their blurb in it. Edit out any of their bits you don't want by simply moving your cursor to the unwanted bit and presseing 'DEL' on your keyboard, then take your mouse down to the area below the quote and start your response/comment.

HTH.... if not: shoot me

blacky · Post by **blacky** » Thu Sep 27, 2012 5:06 pm

I replaced mine with standard style bush's for cost resons at the time & it solved the judder under brakeing

I have standard disks all round but thefronts are now late spec 530d disks with e38 4pot brembo callipers with ferodo ds2500 pads all round

I'm looking at putting this set up on my e36 also as iv done track days in the b10 & not had any brake issues

rcshott · Post by **rcshott** » Wed Oct 03, 2012 1:25 pm

[/quote] I would avoid a different setup as the friction will be different front-rear so will affect the balance under severe braking.[/quote]

Ade has an excellent point here, mixing disc & pad brands is NOT recommended and may possibly encroach on design/transport rules in your country, similar to tyre rules. It may even be against insurance rules! I wonder at the reason for using Red stuff pads? I think they're for track use aren't they? I've been using Green stuff for years, no dust (or very VERY little) for both track & normal driving & have NEVER had fade on track, when other club members complain bitterly about fading using OEM pads... not to mention dust.

As a side note I also replace pads relatively rarely because I use the engine and intelligent driving to slow the car.... brakes are for STOPPING, IMO.

"WARPED DISCS"
This is the 'furfie' of the century & should NEVER occur. EVER!!! Ask any race driver. A long time ago (when I was naive) I got caught by a mec telling me I had warped discs. Much later I found out they weren't warped (or even worn) and the originals were simply cleaned & refitted & i was charged for NEW discs all round!!! A slightly worn disc may give shudder though and if they're worn down by 2mm or more (or whatever the rules are for your country) simply replace them...ALL ROUND. If less than recommended wear, they can be machined (IN CONTROLLED CONDITIONS.... NOT WITH THE "MOBILE" BLOKES).

Discs WILL shatter, almost always on race cars when they overheat & cracks are formed.... at about 1,000 degrees & glowing red hot it's to be expected.

On other than OEM bushes, as mentioned in other posts they WILL make a harsher ride. I tried them in a couple of cars & went back to OEM's.
HTH, Jim.

ade and liz flint · Post by **ade and liz flint** » Wed Oct 03, 2012 2:13 pm

rcshott wrote:"WARPED DISCS"
This is the 'furfie' of the century & should NEVER occur. EVER!!! Ask any race driver. A long time ago (when I was naive) I got caught by a mec telling me I had warped discs. Much later I found out they weren't warped (or even worn) and the originals were simply cleaned & refitted & i was charged for NEW discs all round!!! A slightly worn disc may give shudder though and if they're worn down by 2mm or more (or whatever the rules are for your country) simply replace them...ALL ROUND. If less than recommended wear, they can be machined (IN CONTROLLED CONDITIONS.... NOT WITH THE "MOBILE" BLOKES)..

As you say, Jim, they SHOULD never occur. But they do, sadly. Brief explanation of cause here:-

If the pads fitted within the caliper are not free to move correctly within the caliper as they are corroded/gummed-up/piston seizing/whatever other reason (they usually are free-enough to move to the 'grab' position, but not to freely return and allow a running clearance) they rub on the high spot of the discs without the brakes being applied ie under normal driving conditions (all discs, no matter HOW flat have a high spot - basic engineering fact

). The rubbing of the high spot causes the discs to expand at the high spot as heat is put locally into the disc as the running clearance is incorrect, and when the brakes are applied, the expanded high spot creates a once-per-revolution pulsation into the brake pads/calipers/struts as the pads grab and release the expanded high spot. Usually, the cure is strip the pads from the calipers, clean them all and re-assemble correctly...problem goes away

Loose bushes allows more free movement of the suspension components and the issue is noticeably greater.

The other cause of apparent warp is pads sticking to discs due to water ingress and the pads 'weld' themselves to the disc. This then creates a higher friction point on the discs which grab and release the pads on each revolution under braking until the high friction point is worn away.

Generally, though, I agree with what you say as the discs will not permanently warp UNLESS the local overheating issue is left for too long and local material change takes place through this local overheating. So, if you get brake judder, get them stripped and rebuilt quickly and your issue will disappear...be aware, the 1st few brake applications following the rebuild may still give brake judder until the residual warp (correctly known as residual stress) is removed by even heat transfer through the discs. If it doesn't cure it, you need new discs as they have permanently bent - it DOES happen. I've balanced permanently bent 100Tonne rotors due to localised long-term high friction bending.

Hope that gives some basic insight into thermal dynamic characteristics of rotating components and their effects on vibration

rcshott · Post by **rcshott** » Wed Oct 03, 2012 6:29 pm

Thanks for setting me straight Ade, I didn't know some of that. Cheers, Jim

ade and liz flint · Post by **ade and liz flint** » Wed Oct 03, 2012 11:00 pm

rcshott wrote:Thanks for setting me straight Ade, I didn't know some of that. Cheers, Jim

NP, Jim. It's a simple problem really, which mechanics can make a mint from but which is highly avoidable if the owner knows a few basic facts

Just noticed you're still in Ukraine...how's the car hunt going

rcshott · Post by **rcshott** » Thu Oct 04, 2012 9:45 am

Ade, see PM.

rcshott · Post by **rcshott** » Thu Oct 04, 2012 10:46 am

ade and liz flint wrote: Just noticed you're still in Ukraine...how's the car hunt going

V-E-R-Y S-L-O-W-L-Y! Whilst I began renting in April I've only been here 'permanently' for 7 weeks. There's been umpteen problems with getting married (may actually happen later to day), problems with shipping & auction of furniture in Oz etc, etc, etc.

The marriage thing is very different to Western ways, you get the paperwork together (it's taken 6 months), go to a tiny office & get the 'stamp of approval' & then take it all to Kiev about 6-8 hundred miles away to register the whole thing. I first started all this in February!!! Not sure which country has the most red tape.... maybe Oz.

I went back to Oz early March to sell, pack & prepare my Toy Poodle with needles etc.... WHAT A DRAMA! Anyway the dog arrived Kiev a day later than me as planned, then it took 6 hours to locate her despite the phone number on the cage. We had an o/n train trip to Ivano-Frankivsk & arrived 'home' early am. The dog had 40 minutes at home then fell down the crappy Russian built stairs & broke her neck. So the Huet household has been not too good for several weeks, "Lexi" was with me for 9 years day & night... gone in one second! I suffer from PTSD (thanks to my 4 years of war service & 14 years in the Army), so it's been bloody tough.

Then there's also been many probs with auctioneers & shipping agents as I try to arrange for some sales in Brisbane & have other stuff sent over.... MORE FN DRAMAS.... and continuing. Lucky I've a good strong woman. She's a 44yo doctor skin specialist with own clinic. I've got 24 years on her.

Anyway enough winging! The B10 is in semi-permanent storage whilst the 535i has been on the market....MORE probs & a story for another day, perhaps.
Our house is 5-10 mins from the city. A 2 story solid brick on a 1/4 acre with heaps of apple, plumb, pear & cherry trees. It's a bit old & neglected but at around 40 pound a week rent I aint complaining. Plus, with no car it costs 1.50 pound for a taxi or we can 'slum it' on the bus for about 30 pence for us both.

There (apparently) are no Alpina's available in Ukraine so I'll need to look wider but I'm not too worried until I'm fully settled & then start looking, I reckon after Winter. The trouble is that it's cost me way more than I allowed so we are saving like crazy to build the coffers again, then hopefully I can get something half decent. We'll see. But with my fantastic war pension & things being so cheap here, I don't mind waiting. We are only an hour from the foot of Carpartian mountains and ski resorts (as well as several countries... quite strange for me), we can get a bus for about 4 pounds & stay at a B&B for a week. We've already made friends at the B&B & the bloke has a taxi.... April we spent a day doing a tour of a massive ski resort & he charged be 30 quid!!!

So, mate, that's the short version. Now we're getting over the Lexi loss we are beginning to enjoy Autumn.... Winter.... HMMMM not too sure about it yet. April was -32 but I try to remind myself that it's good cuddling weather!

B10BRW · Post by **B10BRW** » Thu Oct 04, 2012 11:56 am

Jim, Sorry to hear of your sad loss, it must be a very difficult time for you.
Hope you manage to settle in soon and have good luck finding a decent car.
At least you have a good woman to comfort you.
Have you any plans to bring the B10 to the Ukraine?