[Stevie99s]

Hi, please bare with me as this post/problem is a little complicated, many thanks in advance!

Basically a couple of months ago I bought a 325I m sport ( http://www.pistonheads.com/gassing/t...f=47&t=1602180). As far as I can remember, infact I'm sure there was no vibration or problem.

With this being my first auto I did stamp on the brakes a few times thinking it was a clutch....dohhhh 😁 so have done some fairly heavy braking at times.

Now the problem as I remember was when I had my alloys "refurbed and painted" the company borrowed me some se 17" alloys for a couple of days (100 miles) that had a horrible vibration present,especially bad under braking. Now I wasn't too worried as I'd assumed they were buckled etc. And I would have my fresh alloys back soon so fast forward when I got my refurbed alloys back there was still a vibration there although not as bad with the "loan" wheels.

Since then a few weeks back I have had the Mot done which it passed with no advisories, they also rebalanced the front 2 alloys as the painter had just painted over the wheel weights.

I also had a full alignment done which was out slightly.

This still didn't fix it however so my mechanic friend and myself have cleaned the mating surfaces from the wheel/ hub and the wheel bolt holes which were full of flaking paint etc. This I think has improved it slightly but the annoying vibration is still there. 😞

It seems to be worse at 40/50 mph and light braking where it can be quite violent, although it's always there to a degree and I could be wrong.

My mechanic friend did say there was some "runout" on the brake discs, could it be this causing it even when not braking?

Could it be bushes or control arms? The cars got 93k on now.

Any help would be greatly appreciated as I want to get it sorted before a few long trips. Thanks for bearing with me!

[david in germany]

Look at the brake disks for darker spots like these.


If they have darker spots they will need to be resurfaced or replaced. The darker spots in this pic is from very hard braking from very high speeds causing hard spots that the pads skip across causing a violent shake when braking.

Also make sure the weel bolts are torqued the same and properly.

[peter2704]

had similar on mine after having wheels powder coated.I had previously fitted new discs all round.So , new m3 control arms improved it but it was still there,checked new discs and they were out of true(manufacturing issue) so replaced free and all is now good

[raptor_f22]

Had the exact same problem with my car - if you search the threads you'll find my posts. It drove me insane and took ages to get to the bottom of because one mechanic messed me around.
My issue was resolved by changing the rear brake discs.

Can you feel the vibration through the drivers seat as well as the steering wheel? If so, likely to be rear discs. If you do change them stick to a top brand like brembo

[old grey steve]

Stevie re your post there are some common issues re why you get the symptoms you have and where I work ussually see a fair few cars with the very symptoms you're describing but they can occur for varying reasons so I'll give you some of the common one's and I'll leave one that poses a question from your OP for me at least til last.

Brakes if they look like these







i.e. lipped scored corroded its fair game that as the wear sets in vibration can start to become an issue so its worth looking at the brakes, but the telling issue re discs can't be seen as its lip and corrosion issues on the inner faces that can create issues. As you've stated small run out high spots on discs even a fraction of a mm can create issues so as part ofa check everything should be looked at

Re brakes something else worth touching on and over looked time and time again is this the condition of the sliders if these are dirty or contaminated(with paint for instance or corrosion due to lack of cleaning/grease) trust me you'll get vibration. Don't forget the rear brkaes too often over looked but a vibration can travel from the rear to the front do always consider this don't discount this.

Your right to point out the arms



the above ones are common very common and are No9 on the diagram below



also No14 can play apart in some symptoms you get while braking under load, the arms basically move fore/aft due to wear in the bushes you can tap the brake and feel a slight thud for instance when really bad from the outside you can at low speed see the road wheels move/shudder, the arms on No9 are known as tension struts No14 is a known as a lower wishbone.

Re the refurbishment process you say the wheels you borrowed had a noticable vibration but when yours were swapped back though better you were feeling a vibration.. I've seen wheels painted on a car with spray going ovr the discs and callipers this does contaminate the sliders and it does cause issue re braking and thus vibration as said in these cases strip down and a clean of the brkae assembly helps and where suspicion arise repalcement of say pads, discs.

Tyres can become miss shapen they feather on their inner edges this can cuase vibration more so if we are looking at arms with wear and when placed under load can create odd issues so don't discount/rule these out.

But the fav ones to look at are brake assembly and overall brake condition and front arms

Hope this helps a little

[abeardo83]

Do you recommend greasing the sliders Steve? I thought you weren't supposed to grease them?

To the OP: Have you had your GEO checked out too?

[Stevie99s]

Many thanks for the replies chaps, greatly appreciated, especially old grey Steve, 👍. Re the brakes, to me they look pretty much new or newish, however my mechanic friend has said there is quite a bit of run out so I'll get these replaced with new discs/pads.

I've done a few bits & pieces on cars, servicing, intercoolers etc. But nothing on brakes/suspension so forgive my ignorance & million questions 😀

I'm leaning towards pagid discs with textar pads as I understand these are what bmw used originally and can be had at a decent price on ecp.

I see there's a couple of different disc sizes available from my vin so I'll have to measure the disc size, I'm guessing there 330mm and I'm a tad confused as there's a few diff pad sizes available if someone can help there at all?

Re the arms, am I right in thinking that these are parts no 9 & 14 as Steve kindly pointed out above?
Look at this on eBay http://www.ebay.co.uk/itm/251920495197

I'll most likely get original lemforder items, just want to make sure I'm ordering the correct parts?

Hopefully these will sort it out! At 93k I'm guessing the arms could do with being replaced anyway.

Once again many thanks for all your help guys!

[Stevie99s]

Re the wheels being painted/sprayed they were done off the car & the sliders/brakes unfortunately I wasn't there when my friend checked the car but will check of these have been seen to.

Re the geo , yes I had that done a few weeks ago at the Mot, this didn't really make a difference unfortunately.

[raptor_f22]

Stay away from the pagids, an indy fitted them against my wishes and claimed he fitted brembo. The pagids discs are what caused me the issues and I was lucky enough that a more reputable indy was then able to change them for me under supplier warranty or I would have been down over £300

Spend right the first time and you won't regret it believe me

[Stevie99s]

Thanks raptor, I've heard positive and negative things about just about every top manufacturer, brembo,bosch,pagid etc. So may aswell just go with brembo afterall cheers

[old grey steve]

Originally Posted by abeardo83

Do you recommend greasing the sliders Steve? I thought you weren't supposed to grease them?

Simple rule is to ensure that they are cleaned thoroughly before you re build the brake assembly back up hence you take your time when removing/replacing brakes if you clean everything up there is a far better chance that you're not going to get cross contamination issues when the new brakes go back on. I don't get involved with the mechainical side of things that what the boys do but from what I understand its good practice to lightly lubricate the guide pins with silcone based grease(which is good as its provides a decent and effective moisture barrier plus it protectand won'r errodes the rubber elements in the pin assembly) copper grease in this area can create issues as its a petroleum based can attack the ribbers this preventing them from doing their protective job

Originally Posted by Stevie99s

Many thanks for the replies chaps, greatly appreciated, especially old grey Steve, ��. Re the brakes, to me they look pretty much new or newish, however my mechanic friend has said there is quite a bit of run out so I'll get these replaced with new discs/pads.

I'm leaning towards pagid discs with textar pads as I understand these are what bmw used originally and can be had at a decent price on ecp.

Re the arms, am I right in thinking that these are parts no 9 & 14 as Steve kindly pointed out above?
Look at this on eBay http://www.ebay.co.uk/itm/251920495197

I'll most likely get original lemforder items, just want to make sure I'm ordering the correct parts?

If you've got high spots on the disc (run out there are several reasons for this taking place, most of which is reasonably well documented. Again cleaning is key before reassembly its like anything good prep before fitting/application can and usually does return a better result.

Bedding brakes in carefully is key but on this subject there are differing opinions as to how you go about it, which I'll leave alone.

RE what you chose to buy PAgid are well known but we simply won't use it on BMW's and haven;t done so for nearly 3 years for us it was a pain rate of return was high, therefore when you turn over the amount of cars we do and you have brake issues with a certain brand you act upon it, simple rule is on BMW, Mercedes too I won't use/recommend their use, on Textar the situation is a bit better, but these aren't immune either and we've seen issue, hence I try to stay away from their use too now.

If you looking at Euro's look at Brembo(get matching pads though)also look to see once you're disc size is confirmed if they do ATE if they do ATE then thats good as its a known OE supplier for BMW, as is Jurid which you can ususally obtain via GSF for instance so there are choices.

Re the arms the common ones are the tension struts which I placed a picture up earlier but number wise the tension struts(swan neck arm ball joint facing downwards is as you say is No9) the wishbone withthe bal joint facing upwads is indeed No14. Manufacturer wise Lemforders good, TRW are another decent and well respected supplyer both of which you can obtain via Euro, some chose to opt for an M3 upgrade which I've goton mine that are made by TRW once fitted you'll gain a camber advantage the car will feel sharper than the standard set up but decent alingment will be required and I dare say some places will be slightly out on a limb perhaps if you present an non M car with M bits , but if it doubt simply stick to the standard set up

Originally Posted by Stevie99s

Re the wheels being painted/sprayed they were done off the car & the sliders/brakes unfortunately I wasn't there when my friend checked the car but will check of these have been seen to.

Re the geo , yes I had that done a few weeks ago at the Mot, this didn't really make a difference unfortunately.

When I first read the post I thought the wheels were painted on the car (and yes I've seen this done a good few times before ususally by smart repair company's on a forecourt) but when it was mentioned that you had a loan set of wheels that ruled this theory out, but it does happen and paint being sprayed in this area obviously can create issues, like wise seen painted callipers ususally DIY wth paint everywhere on the seals, sliders the lot which again isn't good news. But if you've had 4 wheel alignemnt and there are signs of arm/bush wear it could/should of been spotted and pointed out as carrying out t this procedure with worn arm and saay play in track rods for instance isn't really doing the prodedure total justice but it happens and happens a fair bit.

Originally Posted by raptor_f22

Stay away from the pagids, an indy fitted them against my wishes and claimed he fitted Brembo. The pagid discs are what caused me the issues and I was lucky enough that a more reputable indy was then able to change them for me under supplier warranty or I would have been down over £300

Spend right the first time and you won't regret it believe me

Think you're right mentioned Pagid further up and we don't fit it period, others have and haven't had an issue but I've seen enough to make up my mind and my warranty retunes re brakes are now non exsistant whereas previously due to the brand we were doing far too many, in the end we swapped Pagid for usually genuine BMW parts for instance and never had any further issues and for me that's how I like it. Returns are annoying and really frsutrating when its down to a material issue. Textar don't forget are made in the same factory the materials are slightly different and they seem better but we still saw issues. So again on Textar we tend to steer clear.

If you have the choice and if there's not a price cap genuine is the safer bet, but don't forget Jurid is out there as is ATE and they are OE suppliers