e39 B10 control arms..

skyetripper · Post by **skyetripper** » Tue Feb 06, 2018 11:42 am

I've had a new rear Near Side Rear upper control arm fitted along with a lower swivel joint on the same side (Lemforder parts). As ever after having the parts replaced, I took the car for an alignment check, but they can't get the rear toe in spec on that side.

Doesn't seem to be any wear and tear on any of the other parts and we've changed the eccentric bolt on the front upper arm just in case, but still toeing in a little too much (about 14 minutes outside of limits). Not a massive problem with handling although some wandering and noticeable difference between left and right cornering (and not as good as it was before the new parts). Camber adjusts fine, offside is fine and previous set up before changing the parts adjusted perfectly with room for further adjusting.

Also slightly concerned at the longevity of the Lemforder parts - I'm on the second replacement on each side in less than 30k miles...

Anyone run into this problem before or have any suggestions - driving me slightly nuts!

ali · Post by **ali** » Tue Feb 06, 2018 8:59 pm

It's Lemforder that makes the oem parts for BMW.
Like any other parts though replacement ones it seems never last as long as the ones supplied initially to the factory even from the same company.
It is almost like there are 2 standards of parts, those fitted to new cars that seem to last 70k miles then replacement parts that seem only to last 15k
Just my observations

Ikule · Post by **Ikule** » Tue Feb 06, 2018 10:56 pm

Just had all my suspension done on mine, including the control arms (all Lemforder)
My Indy had no problems with dialing it back in on the settings, so either you've got an out of spec. arm (slightly bent in storage/transit perhaps??)
or stripping it down to replace them has caused another bush to weaken, maybe in the bottom H-arm, that might explain the wandering.
See my reply in the post below (gives part numbers)

http://www.thealpinaregister.com/forums ... hp?t=22269

Hope that helps a bit, good luck.

skyetripper · Post by **skyetripper** » Wed Feb 07, 2018 12:10 pm

Thanks again for the info. Don't think there's an issue with the bottom bushes (camber adjusts as it should and no discernible movement), but get your point about another bush maybe being damaged.

I think the next plan is to replace the upper front arm on the n/s - it's the only arm that hasn't been changed in the time I've had the car so prob worth changing it anyway. (Thanks for the Lemforder numbers!)Don't think I'm ready to go as far as powerflex bushes yet - had mixed experiences of using them on other cars.

Think I'll just have to live with the wear rate, looks like I could replace the Lemforder arms 3 times for the price of a BMW one...

Oneball · Post by **Oneball** » Wed Feb 07, 2018 9:07 pm

Have you got the suspension at ride height when you torque the bolts up?

If you tighten everything with it in the air at full drop itâ€™ll tear the bushes apart in no time.

skyetripper · Post by **skyetripper** » Thu Feb 08, 2018 1:59 pm

Good point - My independent has done most of these recently and they are ex BMW techs, so I hope they're doing it right... I always jack the hub up to take the weight of the car when I've done them in the past.

rc944 · Post by **rc944** » Tue Feb 20, 2018 1:02 am

There are 2 versions of these arms. Earlier ones with a flat mating surface, later ones with a bevelled mating surface. Get the wrong ones and the geo is screwed.

I have an e39 525i sport touring and i learned the above the hard way (almost)

skyetripper · Post by **skyetripper** » Tue Feb 20, 2018 1:14 pm

I wasn't aware of this and I'm guessing if there is a difference, my car is likely to be an 'early' car. (Sept 97, and older round pin electrics)

Having said that - I've checked on RealOEM and they only list one part number and my local (admittedly useless) BMW dealer only lists the one number also.

I've just bought a new Lemforder arm and it has the slightly conical mating surface so I'll just have to see what I find when I come to change it - presumably the face on the hub will be either flat or dished to suit the arm....

Ikule · Post by **Ikule** » Tue Feb 20, 2018 10:35 pm

rc944 wrote:There are 2 versions of these arms. Earlier ones with a flat mating surface, later ones with a bevelled mating surface. Get the wrong ones and the geo is screwed.

I have an e39 525i sport touring and i learned the above the hard way (almost)

I hadn't realised this either so went and did a bit of digging on real.oem and sure enough the earlier BMW part number 33326768791 is listed up to 12/2001 after that part number 33322348886 is then fitted

Pre 12/2001 arm:

Post 12/2001 arm:

The correct (early type) Lemforder part number is 13308 02

with a corroborating parts listing that ties in to the BMW info on Real.oem

For those with post 12/2001 cars the correct Lemforder arm number is 25855 02 which gets you this:

skyetripper · Post by **skyetripper** » Tue Feb 20, 2018 10:42 pm

Great info, and might ultimately be the crux of my problem, but the arm I'm changing is the rear arm. BMW part 33326767831 and No18 on the Real OEM diagrams.

I'll be changing the track control arm next so at least I can make sure I get the right one 👍👍