The Control Arm murderer - United Bimmer Community

**Numark318i** · 07-11-2007, 11:59 PM

Thats who i am.

so far i have put three sets of control arms on my 318 in 65000 miles.

and of course..im due for another set. I love it!

AND AND AND...the 330 is now in need also. Godam. I have only been driving it for 8 thousand miles..and control arm time. of course it has 120k..but still.

ugh.

Its amazing driving over a windy ass road everyday..but it costs me an arm and a leg.

anyone else have this problem? I have read like 2 threads on control arms...wtf.

**Dudesky** · 07-12-2007, 04:08 AM

Wind messes up your control arms? How?

**c1apton** · 07-12-2007, 06:54 AM

I think on the 318 it's your driving habits not the wind. On the 330, it's due for replacements.

**B3M2W5i** · 07-12-2007, 09:15 AM

Quote:

Originally Posted by Dudesky

Wind messes up your control arms? How?

Steering against the winds I assume.

drz · 07-12-2007, 10:16 AM

He meant winding roads. (edit: as in, you know, teh twisties

)

http://dictionary.reference.com/browse/wound

**TerryY** · 07-12-2007, 11:13 AM

At least on the bigger Bimmers the bushings will fail rapidly if the bolts thru the bushings are tightened and torqued while the suspension is hanging down.

You must put the weight of the car on the suspension before tightening to get them to last. Otherwise the internal bushing damping preload is applied in the wrong direction and the bushings are already at the end of their internal travel when the weight is applied to them.

**94bmw325i** · 07-12-2007, 02:28 PM

+1 TerryY

With your control arms going that fast when you do it this time, maybe get some poly ones pressed in?

**TerryY** · 07-12-2007, 05:16 PM

Poly bushings are falling out of favor because of their limited lives with an abrupt failure mode, additional noise transmission and harshening the ride without adding much if any improvement on anything but track cars.

Not being a 3 person--I can usually recognize one though--do the Regular 3s use the same bushing size as the M3 in the same E series?

The trick on the big cars is that E34 E32 and E31 share front bushing sizes. So you go with the E31 aluminum lower arm that has a spherical bearing rather than a bushing (Fits E32 and E31) and an E34 M5 top rubber bushing (Fits E34 E32 E31) and you are beyond anything you could do with Poly for turn in but still have quiet and smooth.

So maybe going to M3 bushings would feel better?

**Numark318i** · 07-12-2007, 07:18 PM

Quote:

Originally Posted by TerryY

Poly bushings are falling out of favor because of their limited lives with an abrupt failure mode, additional noise transmission and harshening the ride without adding much if any improvement on anything but track cars.

Not being a 3 person--I can usually recognize one though--do the Regular 3s use the same bushing size as the M3 in the same E series?

The trick on the big cars is that E34 E32 and E31 share front bushing sizes. So you go with the E31 aluminum lower arm that has a spherical bearing rather than a bushing (Fits E32 and E31) and an E34 M5 top rubber bushing (Fits E34 E32 E31) and you are beyond anything you could do with Poly for turn in but still have quiet and smooth.

So maybe going to M3 bushings would feel better?

yea teh twisties is right.

and ill look into M3 bushings. prolly a good idea.

as far as driving habits I cant do much...could slow down a little, but what's the fun in that.

guess i gotta pay for habits.