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E31 Lower Control Arm

Already documented elsewhere on the internet, but more pictures never hurt!
Problem – clunking sound over bumps from right side of car, visible damage to both ends of control arm.
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Do NOT follow the official BMW instructions for changing this arm as they’ll have you take the entire strut out to gain access to the bolt on the ball joint.  Not necessary.  Instead remove the 3 bolts screen in the above picture and then you can push this lower part (attached to upper arm, lower arm and steering) down to gain access.  These bolts are pretty tight so I cracked them open with the wheel on the ground.  19mm bolts.  It never hurts to spray penetrating oil everywhere the night before either.
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Now you can access the bolt on the ball joint end.  Break out the ball joint tool..
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And if you’re lucky it will come away surprisingly easily!  I was expecting this to be a major problem as the upper ball joints took me days literally – very little tension was required here – no heat required, no 4 ft sledgehammer.
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 The bushing end of the old arm was clearly destroyed, but the ball joint was surprisingly perfect despite the boot being badly damaged for quite some time.  Note that you can’t buy a new bushing for this arm anyway – the whole assembly needs replaced.  Perhaps because this arm is aluminium and pressing in a bushing could easily damage it.

Reassembly is just reverse of above!

You may have heard about having to do the final torque on control arms with the full weight of the car on the ground so the bushes are stressed properly.  You don’t need to that here as the E31 arm has a special spherical bearing, it’s not just a regular bushing.

Should you get an alignment done after this?  Probably, I haven’t so far…  the car was aligned very recently and I don’t see that the alignment will have changed much – I’ll get it checked soon.

Should replace both arms in pairs?  A lot of people will say yes, but there’s absolutely nothing wrong the other side – bushing and ball joint in perfect condition with no play so I don’t plan to do this.

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