Why is my car lopsided - Year 2000 750i Sport Euro Spec

[X606XAR]

Hi,

This UK Year 2000 750i Sport has SLS and EDC.

I replaced the rear shocks four years ago with SACHS equivalents and I have just had the fronts rebuilt by a Polish company called NAGENGAST (https://nagengast.pl/en/about/) for the second time.

Looking at the boot/trunk the right rear side of the car (drivers side in the UK) is lower at the moment and no amount of bleeding this self-bleeding system seems to have made any difference i.e. car in the air rear wheels hanging.

On the driver’s side it is at 597mm from bottom of the 18inch rim to the wheel arch.

On the passenger side it is at ~620 - both measurements done with a full tank of petrol but no load.

I think both sides should be 597mm with 200Kg in the boot - not got a spare 200Kg so can't check.

The local garage has the shocks/struts out at the moment and there are no visual clues as to why (leaks broken springs etc).

If these are the original springs (20 years old in July) then I am hoping that it might just be a tired spring.

If I get in the boot/trunk (105kg) a witness can see the SLS raising the system a bit, and the last time I checked with the wheels in the air we could make the rears go up and down, so in my ignorance I think the SLS is working.

So once BMW UK are open again I can find someone to do a Spring Table lookup (chassis DA63094) and perhaps try that route.

In the meantime anyone got any other ideas about why it is lopsided?

When bleeding/self-bleeding where exactly in the system does the air escape from?

Cheers

Adrian

[CPHES]

How has your experience with Nagengast been? From what I know, the system bleed air back to the reservoir, and air escapes from the vent in the cap. How about the nitrogen spheres, are they good?

[X606XAR]

Not sure how to check the spheres, my understanding from what I've read is that the suspension goes hard when the gas leaves.

But I know I know next to nothing.

Is there any kind of check that can be done on them other than boucing the car around?

[X606XAR]

Re -Nagengast - For 540 euros odd they rebuilt both shocks. First time was about four years ago. This time round just the drivers side was lower (i.e. gas escaped).

The shock cover had got lose and they reckon that sand interferred with the seals.

I'll see how I get on this time.

I use a motorbike for most travel, the car is (sorry was) for continental touring and the missus uses it for the commuting and it is a great shopping trolley.

I am not keen on airports, even less so now, so maybe the continental touring might start again after a trial run to John'O'Groats.

Better change the cabin filters first before I wade through the sea of dead.

[CPHES]

Yes, if not too bouncy in the back, the spheres are likely ok. But I don't know 100% either. here in the US, I can get a pair for about $220, so, I am going to put them on my list. I agree that the 597mm is the correct measurement, and the max difference side to side is supposed to be 10mm. One thought, the leveling bar sits in the middle of the swaybar, are all the bar and end connections even, nothing could be twisted or caught from road debris?

[X606XAR]

Hi,

I put the Bilstein coils on the rear SLS/EDC shocks and that improved the car a lot but it is still 15mm out near to offside.

The front coilfor this car (Vin DA63094) via the spring table are 31 331 091 541.

Which they do not make any more.

So I am looking at all the aftermarket people thinking which one of you will be one of:

A. Too low.
B. Too high.
C. Just right.

Anyone got any evidence backed opnions on this?

Cheers

Adrian

[CPHES]

So, Eibach has a spring kit - 2049-140 - that is what I am looking at. It will lower the car - 30mm at each end. The Bilstein springs you installed may not be EDC compatible ( I know I can't get a Bilstein part in the US that works with EDC ).
look here for some pics - http://www.bimmerboard.com/forums/posts/636513

[X606XAR]

Hi,
I am not worried about lowering the car, some of the dirt tracks I have to use to visit relatives would not be happy.

I got these for the rears which is fitted at the moment on the Sachs EDC shocks I have on the rear:

36-153947:BILSTEIN Bilstein B3 Rear Spring 36-153947 - NMW 7 E38.

Physically they looked the same, and they have lifted the rear - specific for cars with SLS, but no mention of EDC.

Looking more closely at the BMW #31 331 091 541 (https://www.realoem.com/bmw/enUS/partxref?q=31331091541) I can see that this part superceeded part number 31331091523 in June 2013.

That opens up a few different options but none matching exactly my vehicle:

https://www.autodoc.co.uk/car-parts/oem/31331091523

But if I tell this site what the car is it then says these parts do not fit.

I think that parts superceeding one another might by a a bit subtle for after market databases....

May just have to get the Bilstein front coils to match the rears for cars with SLS:

https://www.autodoc.co.uk/car-parts/...ia%5B100%5D=VA

aka Bilstein 36-133314

I may just have to get use to that pick up truck look.

Cheers

Adrian

[CPHES]

Physically they will look similar. The edc part of the e38 suspension calls for progressive rate springs - the spring rate is not linear. That is why I directed you to that eibach spring part. Those springs maybe ok with the SLS / leveling, but are not edc compatible.

[X606XAR]

How would the non-compatability manifest itself?

[CPHES]

It won’t ride as well. Also, the progressive springs from both BMW and eibach are designed to be used with the different edc settings / comfort and sport. I have not tried it, but I know that mixing shocks and springs that are not designed as a working unit can get you odd results.

[X606XAR]

I had a light bulb moment when looking at the Suplex catalogue and my options list.

I have the 337 M Sports Package + S223 EDC but no 704 M sports suspension same as this fellow European:

https://www.bimmerforums.com/forum/s...on-and-springs

So all those enties that say 'Not suitable for Factory Sports Suspension' I can ignore.

Bilstein recon they don't do coils for the this car anymore:

As we do not list an option for EDC, we would not be able to confirm but assuming the fitting is the same there should be no issues – the only difference on the EDC usually is the ability to adjust the damper rates.


The only front options we have listed are the below, but these are actually discontinued:


36-133314 = BMW 1 091 535

And

36-129126 = BMW (31 33) 1 091 543

Not sure if this helps .


------

Other manufactures of progressive springs have expressed doubt and are all suggesting I get them from BMW, which of course don't make them any more.

Waiting on info from Suplex and Eibach.

[X606XAR]

From zfservicedesk@zf.com

Hello,

Thank you for your enquiry.

Springs and shock absorbers are designed to work in unison, with both being tuned specifically to compliment each other. So if the vehicle is fitted wit EDC then it will need springs that have been designed to work with that system.

EDC, is a SACHS system so the correct SACHS springs will work perfectly with these dampers. Unfortunately, ZF no longer bring SACHS springs into the UK market directly. However, Euro Car Parts have a contract to supply SACHS springs so I would recommend contacting your local branch, they should be able to assist you.

I hope that this helps.

Kind regards,
ZF Technical Support


So Euro car Parts in the UK is out of stock but autodoc (German with a UK frontfacing web page) has them for £52 ish each.

[CPHES]

With edc, you have the original Boge shocks - rebuildable by nagengast in Poland, and eibach or H&R - both of which will lower. You could see if schmiedmann can help you.