New control arms: Meyle/Lemförder/TRW?

[megastihl]

Greetings.

For my 730i I was removing the control arms, to replace the bushings (with the stronger 750i bushings). I noticed 2 of my arms had a damaged rubber over the rod, so these arms need to be replaced. I also noticed that one of the rods (with no damaged rubber) is moving kinda stiff, like it's not lubricated enough. Something I should worry about? Replace it, or just put it back?

Now, about those that need to be replaced... I know that most people swear by Lemförder, but these control arms are, in my case, literaly twice the price of the TRW or "Meyle OEM qualiy" control arms. Is it worth the money, or will a TRW / Meyle do just fine?

[shogun]

TRW or Meyle should be fine, I personally would try TRW or RUVILLE, have read some good comments on a German forum.
At the moment I have Febi Bilstein installed, also the steering center link, no problem so far. Lemforder and TRW are now anyway in the same ZF group.
Ruville now belongs to the Schäffler Group in Germany which also owns the brands INA, FAG and LuK and the majority of Continental

The rubber caps for the rods you can get from one shop in Germany https://www.car-parts24.com/Axle-Steering-parts-BMW-e32
About 10 years ago I found a supplier for that in Denmark and I told them where to get them and now they have them always on stock
Gummimanschette für Traggelenk 33 x 15mm Item number: 85013315 Category: Axle and Steering parts EUR 2.99/piece
Gummimanschette für Spurstangenkopf/for steering link 29 x 14mm Item number: 85012914 EUR 2.99/piece
This ebay shop in Germany also has a lot of these rubber caps, maybe there is a fitting one https://www.ebay.de/str/You-S-Online...cat=8748958016

[megastihl]

this has been VERY helpful. Thanks for the reply shogun

[unity]

I avoid Meyle at all cost. To me they are just one step above URO - which is the worst.

I always prefer Lemforder as its typically OEM. TRW I would consider and have used often on American cars, as TRW is often OEM for Ford. Moog is another popular one, I think generally good but its seem they are not what they were 10 years ago.

- - - Updated - - -

Oh, and if you want REALLY good bushings then check out Moosehead Engineering (not affiliated). They make metal spherical bushings. I put a set on my 750iL and they are not nearly as harsh as expected. In fact, I often forget there are even there.

[megastihl]

another thing. I just noticed that the front arms (not those with a bend in it) give 2 options in realoem. Steel or aluminium. The thing is: on the right side I have OEM alu, while on the left side I have a steel one, from an unknown brand. Just curious what the difference is between them, and why they have 2 options. Is it best to match left & right with the same materials?

[shogun]

alu is lighter, it is said that they once made that to reduce the weight to eliminate front vibration problems. I only use steel ones, cheaper. weight difference is1 kg to 1.6 kg per wishbone.
Parts catalog says to use alu or steel on both sides, no mixing.
Another advantage is that the rubber bush 31 12 1 124 622 can only be replaced on the steel wishbone (not on the alu version) http://bmwfans.info/parts-catalog/E3...pport_wishbone

[megastihl]

alu is lighter, it is said that they once made that to reduce the weight to eliminate front vibration problems. I only use steel ones, cheaper. weight difference is1 kg to 1.6 kg per wishbone.
Parts catalog says to use alu or steel on both sides, no mixing.
Another advantage is that the rubber bush 31 12 1 124 622 can only be replaced on the steel wishbone (not on the alu version) http://bmwfans.info/parts-catalog/E3...pport_wishbone

The latter ain't correct, as I just (as in 2 hours ago) swapped out the bushing out of the alu wishbone. Still not sure if I would leave the steel one in, or swap it for another alu. (as the alu I have is OEM, and the steel one I have has no brand on it, so I would swap that one out then)

[shogun]

The BMW parts catalog clearly mentions, that the rubber bush is NOT for the alu wishbone: Steel rubber mounting 31121124622 −Info: ONLY applies to (#13) Wishbone, left, steel 31121139991, (#13) Wishbone, right, steel 31121139992.

[megastihl]

Hmm indeed it says that. But it's strange, I just replaced the bushing myself and it doesn't seem like it wasn't meant for it.

[unity]

I think because aluminum arms are generally a one-time press. Aluminum is softer and can deform were cast steel is not forgiving. It can even crack. My guess is they maybe consider too much potential damage from being pressed more than once. First time is original install, then removal is more stress, then a third time for the second new one. Or maybe a special pressing processes is required that shops dont have. Just a guess but I have see this mentioned before with other parts. But if you think it pressed fine and wont spin out and the aluminum did not crack you may be just fine.

[megastihl]

I think because aluminum arms are generally a one-time press. Aluminum is softer and can deform were cast steel is not forgiving. It can even crack. My guess is they maybe consider too much potential damage from being pressed more than once. First time is original install, then removal is more stress, then a third time for the second new one. Or maybe a special pressing processes is required that shops dont have. Just a guess but I have see this mentioned before with other parts. But if you think it pressed fine and wont spin out and the aluminum did not crack you may be just fine.

I had them replaced with a hand press, something similar to this http://www.williammaloney.com/LandRo...ushingTool.jpg
It didn't require any force, it came out & back in easily. So tbh I don't think this will cause a problem.

[shogun]

I have seen that too by one of my wrenching buddies using my press and removing the bush and install a new one on a alu wishbone. He also had no problem, but officially not....
Probably the reasons unity mentioned, difference between the alu and the steel arm material.

[unity]

Could also be liability. Again, BMW thinks the aluminum is too fragile to risk it - at least with their shops.

FYI, I might have my original set of arms if you need the other to rebuild. Then you have a proper set. Let me know your location. Just pay shipping.

[Sansouci]

It may be the same difference with steel vs aluminum floor jacks under load: the steel will deform before breaking while the aluminum (if cast) with break without sufficient warning. They also have different dampening characteristics although the bushing takes out the vibration.