E31 suspension rebuild illustrated

[clockwork]

SO factory rear springs for e31 (no CSi) are stiffer than H&R huh. Nuts.
Maybe I should put my factory ones back in and that may help for the "difference in drop" compared to the H&R springs in the front too.
has anyone here kept factory rear springs and installed aftermarket springs only in front?

[rogbmw]

I have never seen a front McPherson strut taken apart without a spring compressor. So...you are saying you did it with no spring compressor? Neat! Damn...now just more stuff to take apart and clean......

[olinjohnston]

I have never seen a front McPherson strut taken apart without a spring compressor. So...you are saying you did it with no spring compressor?

It is actually the easiest and safest way to get them apart since your face and body are never in range of the tensioned spring. You just slowly lower the strut and the spring decompresses. Once you swing the strut out sideways, you can swap the strut insert/spring and just jack it back up into position. The top mount stays in place.

[TxGR8White]

+1 on the spring removal tip - that is how we do it at SPM.

[Luisclassic]

I just rebuilt my front end too. Control arms, draglink, tie rod ends, steering ends, lower wishbone and new Bilsteins B6 Sports shocks. I had the springs sent in to a local spring works who dropped them by 30mm and stiffend them up. Must say the front end handles so much better after spending time and money on it.

Im now looking at doing the rear, I already put in Bilsteins B6 at the rear as the shocks were collapsed about 2 months back and inserted the strengthening plates on the shock towers that were torn on mine. Didnt have the time to do the full strip down but I am very keen to get started.

[m6bigdog]

SO factory rear springs for e31 (no CSi) are stiffer than H&R huh. Nuts.
Maybe I should put my factory ones back in and that may help for the "difference in drop" compared to the H&R springs in the front too.
has anyone here kept factory rear springs and installed aftermarket springs only in front?

I suggest you install the BMW Euro M-Sport rear springs BMW p/n: 33 53 1 138 738 with the H&R fronts. The M-Sport rear spring rates are a good match with H&R front spring rate. The stock rear springs are better than the H&R rears but are still too soft to work with the H&R fronts. The issue with H&R in total is they leave very little suspension travel and the suspension is close to riding on the bump stops. Hey who knows what the H&R suspension engineers were smoking when they designed their E-31 spring set? Low slung isn't everything since you still need a suspension!!! So guess what? Eibachs are stiffer but for cornering performance they are hardly any better. The best is BMW Euro M-Sport Springs all around (BMW M Division design) and if you want a great performing suspension you'll also get the M-Sport Dampener that 100% match the springs. Front M-Sport Spring 31 33 1 138 735. BMW M-Sport front strut 31 31 1 139 653/654 and rear dampener 33 52 1 137 474. After that the CSi is an even stiffer spring set however I would only use the BMW CSi dampeners and forget the Bilstein universal dampeners.

[nervnom3]

I have M-Sport springs all around on my car with Bilstein shocks. Excellent balance of handling, comfort and stance. Check sig bellow.

[clockwork]

thanks M6bigdog. I'll have to look into those, for sure!!!
I just happen to have my factory 850i springs sitting around and was thinking of installing them agian, OR even cutting off a coil to make it stiffer/sit more equal with the H&R front springs, but not if it's going to upset the balance of the ride over bumps.
again, thanks for the part numbers.

[ride850i]

Great info. I will be doing mine soon.

[DMPrentice]

I have a set of rear springs "allegedly" from a EURO 850, the part number stamped on them is bmw 1138 112 LP 051... They have 10 coils and are a bit shorter than the H&Rs,, does anyone know this part number ??

[revtor]

DMPrentice: 33 53 1 138 112 - Appears to be the rear springs for pre-April 1992 ECE-spec 850i with electronic damper control (EDC).

[acheson850i]

Hi Folks, I have googled and searched this forum for information on front suspension overhaul or rebuild. Being a relative newbie, if someone could point out the bushings/bearings that most likely need to be checked or replaced from the diagram in post #20 (i.e. #s 2, 23, 15/16 and 7 ??) of this thread that would help. I don't want to spend a bucket load of money for specialized tools either. I do plan on doing the wrenching myself though. Any other links would be helpfull also. Thanks I appreciate everyone's advice here.

[jcs1966]

Typically, upper and lower control arms, sway bar links, and sway bar bushings. Tie rod ends if they look bad. I would change the control arms vs just the bushings. If you afford it, get Wokke's spherical bearing uppers, if not, Leomforder is the preferred mfg for all of the above

[acheson850i]

Jeremy, Thanks, man i must be tired, i just realized i was looking at the diagram for the rear suspension... similar advice, i presume applies to the front suspension. Leomforder and Wokke it is then! Thanks! Good stuff here!

[deaven]

thanks for the info... will come in handy

[Omega man 1969]

It is actually the easiest and safest way to get them apart since your face and body are never in range of the tensioned spring. You just slowly lower the strut and the spring decompresses. Once you swing the strut out sideways, you can swap the strut insert/spring and just jack it back up into position. The top mount stays in place.

Very true....I was once removing a spring off a strut on a bench .....the strut was held in a vice at the time. The cheap spring compressors jumped off and the force was unbelievable. It flew across the workshop and hit a big dent in the steel fire door. If that had hit me I doubt I'd be here now. My other lesson was getting under a car using only a scissor jack, I was trying to look at the steering rack on a Delorean of all cars. I couldn't quite get my head in the right place so I got out from under the car .....I only got about half a turn on the jack before it snapped!!! very lucky escape.

[Fatandre]

Wow Omega. Scary stories

[olinjohnston]

My other lesson was getting under a car using only a scissor jack

[clockwork]

so I just did the rears. noticed the rear of the car was sagging (2" gap in front suspension, 0.5" gap from tire to wheel's fender) so I cut half of a coil on my factories ad went to install. THEN I realized I have Eibach's and not H&R's after all.
Anyhow, does the car need to be on the ground (suspension loaded up) before I tighten the offset bolt and nut in the rear subframe? I'm guessing so with factory bushings (no Wokke specials installed yet)...

[wokke]

As a general rule:
if a rubber bushing is installed you have to preload = car on the ground (or 4-post lift).
If a spherical bearing is installed like in upper & lower wishbones on the rear axle no preloading is required.
I don't know what offset bolts are but if you mean the eccentric bolts for the rear axle adjustment you can tighten them without preloading.
For a correct job though a four wheel alignement is required once those bolts have been openend.

[clockwork]

As a general rule:
if a rubber bushing is installed you have to preload = car on the ground (or 4-post lift).
If a spherical bearing is installed like in upper & lower wishbones on the rear axle no preloading is required.
I don't know what offset bolts are but if you mean the eccentric bolts for the rear axle adjustment you can tighten them without preloading.
For a correct job though a four wheel alignement is required once those bolts have been openend.

thats what I thought Wokke, Rubber needs to be pre-loaded/spherical does not.
and yes I meant the eccentric bolt/washer as shows as part $2 in the diagram1.jpg

I will be getting a 4 wheel allignment in a few weeks, as soon as I put new front shock mounts in. I sheared one off when I hit a pothole.
e31 front right shock mount sheared on sept 30 2013.JPGE31 front right shock mount sheared sept 30 2103.JPG

[clockwork]

can the rear shocks/struts be removed from the car without having the drop the exhaust (mine is all one welded piece from headers back to mufflers) OR not removing the wishbone?
I don't mind loosening the exaust from the hangers from mid point back, just trying to avoid removing the entire exhaust again... its a huge PITA.
I just got a wheel alignment yesterday and I want to now buy/install the Phoenix motorsport rear shock/strut bump stops but was hoping I could just undo the 2 nuts (in the wishbone) by the rear wheel hub and not undo/loosen the top of the wishbone (in the cross member) and perhaps the wishbone would sag enough (probably would strike the muffler pipes) to allow me to remove the strut/shock to allow for install of the dust cover and bump stops.
Thoughts?

[Larkin660]

I will be getting a 4 wheel allignment in a few weeks, as soon as I put new front shock mounts in. I sheared one off when I hit a pothole.
<img src="http://forums.bimmerforums.com/forum/attachment.php?attachmentid=495049"/><img src="http://forums.bimmerforums.com/forum/attachment.php?attachmentid=495050"/>

That must have been one nasty pothole

[clockwork]

Larkin, you have NO idea, and I pray no one ever has to. thank god it was a CHEAP/SUPER easy fix.
an excuse to install my front K-Mac sway bar. rear to be installed some other time

[Luisclassic]

so I completed my rear end rebuild,

thread link
http://forums.bimmerforums.com/forum...ar-End-rebuild