Differential Diagnosis: FCAB vs Wheel bearings

[TigerTater]

So I recently started having a noise coming from the front end at low speeds <30mph, sounds similar to a bad hub I had on my truck previous to the ZHP. Did some research pulled the tires to check the hubs, they don't really sound that bad compared to the youtube videos Ive seen. I also examined my tires and believe that I am having some "feathering" or "cupping" not sure which (looking at the pictures the inside tire track is the the left side margin of the page). These apparently are attributed to worn out suspension components...leading me to my next idea the FCAB's. I saw videos on these being worn out and while I do not think mine are that bad, I believe they need replacement. In the video below you can see them move...Im assuming this is more than normal? :shrugg: Anyways...filmed it with my phone...at the beginning I was shaking it mildly, then got more aggressive at the end...Let me know y'alls thoughts:shifty

http://youtu.be/JXBLrJ3EFVk
http://i242.photobucket.com/albums/ff47/ewhit26/IMG_1464.jpg (http://s242.photobucket.com/user/ewhit26/media/IMG_1464.jpg.html)
http://i242.photobucket.com/albums/ff47/ewhit26/IMG_8432.jpg (http://s242.photobucket.com/user/ewhit26/media/IMG_8432.jpg.html)

[Vas]

OEM bushings or have they been replaced before? If they have been replaced how long ago and with what brand?

[BCS_ZHP]

From your video, I would think FCABs. You say you were shaking it aggressively at the end. Think about it, if you're 200 lbs you might have gotten 1/4 to 1/3 of your weight into that shaking, so 50-65 lbs of force. You car weighs about 3200 lbs, say each corner is 800 lbs, every bump & imperfection in the road is subjecting that FCAB to 12-15 times the force you were shaking into it. After new FCABs, you will see no movement of the LCA inside that FCAB.

And if you want your front suspension real tight, do the same thing and look at your tie rods. Our cars also get some play in the tierods such that they can be wandering and cause tire scrub. But if your issue is inner tire wear, then you might be running too much negative camber.

[TigerTater]

From your video, I would think FCABs. You say you were shaking it aggressively at the end. Think about it, if you're 200 lbs you might have gotten 1/4 to 1/3 of your weight into that shaking, so 50-65 lbs of force. You car weighs about 3200 lbs, say each corner is 800 lbs, every bump & imperfection in the road is subjecting that FCAB to 12-15 times the force you were shaking into it. After new FCABs, you will see no movement of the LCA inside that FCAB.

And if you want your front suspension real tight, do the same thing and look at your tie rods. Our cars also get some play in the tierods such that they can be wandering and cause tire scrub. But if your issue is inner tire wear, then you might be running too much negative camber.

Yea your right...time to change them.

OEM bushings 84K on the odo.

Would an alignment be enough to correct the toe/camber?...the rear tires are fine, I rotated them today as well.

[ELCID86]

Are those tires not directional (one way)?


Thumbs, iPhone, Tapatalk.

[TigerTater]

Are those tires not directional (one way)?


Thumbs, iPhone, Tapatalk.

:facepalm:facepalm:

yes they are. How do I rotate them since I am running a non square- OEM setup?

[QC_ZHP]

Can you even do it? Aside from dismounting.

[BCS_ZHP]

No, you cannot rotate a directional staggered set up. Just get prepared to replace your rear tires every 17-20K miles and your fronts half as much.

[blalor]

Your video's of the control arm bushings; where's the "ftab" term coming from? I just replaced mine and it was a pretty easy job (and I didn't buy replacement brackets; I had access to a hydraulic press). I've read that they tend to wear out after 30-40k miles. As replacement parts go, they're pretty cheap. :-)

[ELCID86]

No, you cannot rotate a directional staggered set up. Just get prepared to replace your rear tires every 17-20K miles and your fronts half as much.

Or as stated, remove from rim and reverse the rubber.


Thumbs, iPhone, Tapatalk.

[TigerTater]

Your video's of the control arm bushings; where's the "ftab" term coming from? I just replaced mine and it was a pretty easy job (and I didn't buy replacement brackets; I had access to a hydraulic press). I've read that they tend to wear out after 30-40k miles. As replacement parts go, they're pretty cheap. :-)
Your right...I miss typed...I corrected my original post...Can't change the title of the thread (mods may if they please). How difficult was it to get them pressed in? Did you bring it to a shop or DYI? What brand did you get? Im leaning towards these: http://www.ecstuning.com/BMW-E46-330i-M54_3.0L/Suspension/Bushings/ES2651031/ is it what most people run? OR these: http://www.turnermotorsport.com/p-1870-front-control-arm-bushings-fcab-meyle-hd-rubber-e46-z4-not-m-models-pair.aspx

[danewilson77]

PM me with how you want it to read. Thanks.

Sent from my SCH-I545 using Tapatalk

[blalor]

Yep, I used the purple Powerflex ones. I bought them from Bimmerworld without the bracket/housing.

http://cdn.nexternal.com/bimmerworl/images/PF_4601_300.JPG (http://store.bimmerworld.com/powerflex-e46-3-seriesz4-control-arm-bushing-p281.aspx)

If you choose to buy them already pressed into a new housing it's a piece of cake, as they just bolt off/on. You'll still need a 3-jaw puller or similar to get the old bushing off the control arm. If you choose to press the new ones in, it's pretty simple, but you'll obviously need a press of some kind. Getting the old bushings out was a bit of a pain: the factory ones have a fairly thin metal sleeve that I had to cut/bent/punch out as I didn't have a socket big enough to push it out with the press.

[BCS_ZHP]

And buy the new bolts that attach the FCABs, they're supposed to be one-time use, they're fairly cheap.

[blalor]

You're also supposed to replace the bolts that hold the aluminum subframe reinforcement plate in place. :-(

[BCS_ZHP]

Right, so it's about 10-12 bolts total that you need to buy. And if you don't, then don't use an air gun when reassembling cause you'll likely snap one off (ask me how I know that).

[TigerTater]

Right, so it's about 10-12 bolts total that you need to buy. And if you don't, then don't use an air gun when reassembling cause you'll likely snap one off (ask me how I know that).

Ha. Thanks for the heads up. Do most kits come with the bolts included? And did you go Meyle or Powerflex...Ive read different things about going too stiff with the powerflex causing excess vibrations..?

[BCS_ZHP]

Bolts are a separate purchase from your local dealer, IIRC less than $2 each.