Alloy wishbones

[Rich25i]

Hi
I have a 89 325i and was wondering if the wishbones were alloy?

If there not what gains or losses would be found if i fitted some?

[dazleeds]

only genuine touring wbs are ally

[Andy325i]

Very doubtful unless anyone has changed them

The alloy ones are lighter (and maybe stronger)

As "standard" they only came on M3's and some tourings?

I think I spoke to someone a while back who said that the ball joints are not replaceable on the alloy arms, hence if you get a shagged balljoint the arm needs changing?

Not sure how true this is?


Andy

[Rich25i]

Thanks for your help so far.

I have a touring that im breaking

Rich

[JazzMan]

I think I spoke to someone a while back who said that the ball joints are not replaceable on the alloy arms, hence if you get a shagged balljoint the arm needs changing?

Not sure how true this is?


Andy

On E46's you replace the whole arm, they are ali. It maybe that its just more econmoical to replace as a whole rather then pressing out the old ball joints and replacing them.

[Turbo-Brown]

My guess would be that they force you to change the whole arm to avoid fatigue failure of the arms.

Aluminium doesn't have a fatigue limit which means that if you keep on stress cycling it, it WILL fail, whereas steel does have a fatigue limit so as long as the stress remains below that limit, they'll last indefinately (in theory!)

[Demlotcrew]

No,

The ball joint is incorporated into the arm where as on the steel ones the ball joint is pressed in as a seperate item.

The alloy arms would outlast the steel ones and are very light (less than half the weight) and are much much stronger.

But at £230 a pop from the dealers

Andrew

[JazzMan]

You can get Febi/Bilstein ones for the E46 that are a lot more cost effective than the ones from the stealers. There's supposed to have better ball joints too that wont wear out as quickly as the OEM items. Maybe they do E30 ones too?

[Turbo-Brown]

No,

The alloy arms would outlast the steel ones and are very light (less than half the weight) and are much much stronger.

Andrew

Don't confuse strength with fatigue life.

Stronger they may be, but stick them both on a test rig and cycle them within their design limits and the alloy arm will fracture at some point, irrespective of the outright strength of each arm.