Front lower suspension aluminum vs steel question

[dadysev]

Are there certain models that have aluminumn suspension parts over steel? i'm Talking about the control arm and radius/thrust arm.
I see a combination of both and for parts also.

[philly42]

Originally Posted by dadysev

Are there certain models that have aluminumn suspension parts over steel? i'm Talking about the control arm and radius/thrust arm.
I see a combination of both and for parts also.

Didn't know they made both for the E70. performance will improve in all areas include MPG in saving weight. But aluminum parts aren't as strong as steel

This reminds me of some E30 and E36 models that were fitted with lighweight parts from the factory for competition. I will be fitting these aluminum control arms to my Z3M. They maybe half the weight of the steel counterpart.

[dadysev]

Originally Posted by philly42

Didn't know they made both for the E70. performance will improve in all areas include MPG in saving weight. But aluminum parts aren't as strong as steel

This reminds me of some E30 and E36 models that were fitted with lighweight parts from the factory for competition. I will be fitting these aluminum control arms to my Z3M. They maybe half the weight of the steel counterpart.

Same on the e46, e60, F10, but it seems BMW uses steel arms in the front when xdrive is present. Most likely for the added forces/torque in the drive of the front wheels.

[9vapors]

I don't have much to the answer, but I can share a few pics of my 2012 X5M when I was having the lowering springs installed...mine seem to be Aluminum.

John

[mitch808]

Originally Posted by philly42

Didn't know they made both for the E70. performance will improve in all areas include MPG in saving weight. But aluminum parts aren't as strong as steel

This reminds me of some E30 and E36 models that were fitted with lighweight parts from the factory for competition. I will be fitting these aluminum control arms to my Z3M. They maybe half the weight of the steel counterpart.

This is not entirely true. At least not a good blanket statement for all cars.

Case in point, The Subaru STi came with cast aluminum a-arms. The WRX came with stamped steel arms. The aluminum weighed more and was stronger.

[heatmizr]

For a locating member or one under tension, alum might be fine. (EDIT - like upper arm pictured above)
For a vehicle of this size/weight, if stock was steel, I would want to do some math before replacing more serious / stressed parts with aluminum. (EDIT - like the lower arm, which is the more stressed member in this arrangement)

*EDITS - added to include what I meant as pointed out below

[dadysev]

Originally Posted by 9vapors

I don't have much to the answer, but I can share a few pics of my 2012 X5M when I was having the lowering springs installed...mine seem to be Aluminum.

John

Thats the upper arms. They are all aluminum. i'm talking about the lower control arm and thrust arm.