BMW M5 Forum and M6 Forums banner

1 - 4 of 4 Posts

·
Registered
Joined
·
970 Posts
Discussion Starter #1
Can anyone give me an explanation as to why the front suspension wishbone is different between cars upto 06/1994 and those afterwards? Those after '94 have a steel wishbone (part no, 31 12 1 139 991/2), which is cheaper than the aluminium one fitted to the prior M5's (Part no, 31 12 1 139 987.8.


Is it an upgrade that could be fitted to all E34 M5's?

Does it have something to do with the larger wheel/brake configuration?


Suggestions/Answers most welcome.

Thanks Chaps!

Regards

Brian
 

·
Registered
Joined
·
176 Posts
You answered your own question, it's cheaper. Plus the steel one is slightly stronger, if slightly heavier, considering they did go out with a bang on the last year's run (1995) with the mad 3.8's. All things considered, unless you live in an area riddled with potholes and rather distorted roads, or have more or less converted your car to a race car, the aluminum one should hold up just fine without bending or breaking, saving you some money from having to switch to the steel unit.

On an interesting note, the E30 M3's did the opposite switch in about 1990, going from steel to aluminum control arms.
 

·
Registered
Joined
·
970 Posts
Discussion Starter #3
Hi Hollis,

Sorry, maybe I wasn't clear? The earlier aluminium unit is a lot more expensive than the later steel unit.

I also thought the later steel unit would be stronger, maybe to cater for the added weight from the larger calliper/Discs.

Thanks

Brian



Hollis said:
You answered your own question, it's cheaper. Plus the steel one is slightly stronger, if slightly heavier, considering they did go out with a bang on the last year's run (1995) with the mad 3.8's. All things considered, unless you live in an area riddled with potholes and rather distorted roads, or have more or less converted your car to a race car, the aluminum one should hold up just fine without bending or breaking, saving you some money from having to switch to the steel unit.

On an interesting note, the E30 M3's did the opposite switch in about 1990, going from steel to aluminum control arms.
 

·
Registered
Joined
·
176 Posts
yewcorner said:
Hi Hollis,

Sorry, maybe I wasn't clear? The earlier aluminium unit is a lot more expensive than the later steel unit.

I also thought the later steel unit would be stronger, maybe to cater for the added weight from the larger calliper/Discs.

Thanks

Brian
Ok, now that would make more sense, thanks for clearing that up. Yes, the steel one is a bit stronger (less flex), and costs a bit less materials wise, so it would make sense to use it instead of the aluminum ones at the minor cost of a couple of pounds of weight.
 
1 - 4 of 4 Posts
Top