E46 Fanatics Forum banner

XI Suspension Guide

205K views 283 replies 104 participants last post by  minengr 
#1 · (Edited)
I'm sick and tired of seeing thread after thread on suspension so read this first. If there are any changes needed to this guide please let me know.

First statement: RWD suspension is NOT the same. If you read in the general forum that H&R springs are super comfortable or Eibachs will slam your car, that is NOT true for the Xi. Xi models have less suspension travel than the RWD models and therefore have different ride comfort characteristics. This also means that you CAN NOT use parts (none of them so don't ask) from a RWD car on an Xi. They have different suspension geometries and dimensions so please confirm any advice you get in the General E46 forum before you buy stuff as it's likely wrong...or just read this guide. With me so far? Ok, read on.

In general you have three options:
1.) Replace your suspension with an OEM replacement. This will be the most expensive option and will not lower your car at all. Depending on how long it has been since your last suspension replacement, it may even raise your car. This set up will have a very soft ride with quite a bit of body roll but will be able to go over any obstacles that may come your way. It also makes it quite a bit easier to jack your car up since you won't have to drive up on 2x4s to get the jack under your car. Remember that you can replace the shocks/struts with aftermarket components and still use OEM springs if you should desire.

2.) Replace your suspension with aftermarket shocks/struts and springs. This option is the cheapest way to go and will lower your car a moderate to high amount depending on what spring you buy. The shock/strut has very little to do with the ride height so we'll start with springs. There are, in general, two options for springs on the Xi. Eibach springs lower the car a moderate (0.75"-1" ) amount while retaining much of the comfort that OEM springs would give you. This seems to be the best option for many people on the forum because we daily drive our cars. This will be similar ride height to a RWD sport package. If you don't and want more performance, H&R is the next set. H&R springs lower the car a high amount (1.5"-2" ) but substantially degrade the ride comfort that you would get out of your car. This ride height will be similar to a RWD ZHP. This option is good if you autocross/track the car and don't use it for your daily driver or if the roads where you live are flawless (but then you wouldn't have an Xi anyway right?). For shocks/struts you, in general, have two options. Koni shocks/struts are the most expensive choice but they are adjustable and the rear ones tend to be a bit more reliable than the Bilsteins. If adjustability is what you're looking for, look no further than the Konis. I personally have them and love them. Konis are ok for cars lowered a lot to not lowered at all. The second option is Bilsteins. They are cheaper and not adjustable but the rears tend to leak. There are reports that running E36 M3 rear shocks will solve this problem but that increases the cost. (Thread: http://forum.e46fanatics.com/showthread.php?t=830014) Bilstein shocks come in both "Sport" and "HD". The "Sport" models have a shorter stroke and are better for cars that are lowered a lot. The "HD" models have a longer stroke and are better for cars that are moderately lowered or not lowered at all. There are other shock/spring manufacturers out there but I cannot vouch for them nor have they been vetted by the forum. If you are someone who has experience with other manufacturers, please let me know and I will update this.

3.) Replace your suspension with coilovers. If you want to go this route, ensure that you get a kit that is designed specifically for the Xi models. Coilovers provide adjustment in ride height on the fly and also provide the most substantial ride height reduction (yes you can "slam" your car with this). However, they do tend to be uncomfortable and more jarring than any other option and also have a tendency to wear through CV boots quickly causing potential front axle failure. They are more expensive than shocks/springs but cheaper than OEM. Also consider that you might need camber plates and arms to compensate for the drop unless you don't like even tire wear.

Please, please, please, please do NOT buy Raceland coilovers or any other cheap shiity parts you find on eBay. They are cheap for a reason and I really would NOT buy crappy parts when it comes to the only thing that's holding your car up. There have been documented failures on these parts and they pose a substantial safety risk to yourself and others if you install them. That said, if you still feel as though you want to buy and install them after this warning, then it's your car and up to you.

Some people have asked if they can combine aftermarket and OEM components for their suspension and the short answer is that it depends. The long answer is that if you want to replace your springs and run OEM shocks/struts then you'll have issues. The OEM shocks/struts are not valved appropriately for the aftermarket springs and will wear out quickly. If your question is how quickly, I don't know as that depends on a lot of things. If you want to run aftermarket shocks on OEM springs, go for it as long as the stroke of the piston is long enough (Bilstein HD works great).

If you are going to be doing a suspension replacement, ensure that you purchase all new hardware to perform the task you are doing. This includes the upper mounting nuts, lower mounting bolts, etc. Also purchase new upper shock/strut mounts and rubber bushings. You can reuse the bump stops however they will need to be cut approximately 0.75" if you are lowering the car.

For more firsthand ratings on what people think of different options, check this link:
http://forum.e46fanatics.com/showthread.php?t=731343

For DIY Instructions follow this link:
http://www.bmw330ci.net/projects/suspension.php
The car is a RWD car but the method is the same.

Parts you will need if you want to do a complete refresh:
07119900402 - Rear Lower Shock Bolt x2 (Required)
33521136283 - Rear Shock Protector Tube x2 (Optional)
33531094518 - Rear Lower Spring Pad x2 (Optional, replace if yours is damaged)
33531136385 - Rear Upper Spring Pad 5mm x2 (Optional, replace if yours is damaged)
33531094754 - Rear Upper Spring Pad 14.5mm x2 (This is the thicker version of the one right above, pick one or the other - Optional, replace if yours is damaged)
33526772864 - Rear Shock Mount Gasket x2 (Required...unless you like water in your trunk)
33531136395 - Rear Bump Stop x2 (Optional)
33521092362 - Rear Upper Shock Mount x2 (Highly suggested)
07119905374 - Rear Upper Shock Mount Nut x4 (Highly Suggested)
31356778832 - Front Lower Strut Bolt x2 (Required)
31336752735 - Front Upper Strut Mount x2 (Highly suggested)
31331091867 - Front Upper Spring Bushing x2 (Suggested)
31331096664 - Front Lower Spring Bushing x2 (Suggested)
31311139453 - Front Strut Mount Cap x2 (Optional, replace if you lost yours)
31336752832 - Front Bump Stop x2 (Optional)
31316769731 - Front Upper Strut Mount Nut x6 (Highly Suggested)
31106774714 - Front Upper Strut Nut x2 (Suggested)

Koni Part Numbers:
8741-1481RSPORT x1
8741-1481LSPORT x1
8040-1343SPORT x2

Bilstein Part Numbers:
24-024532 x2 (Rear HD E46)
24-024532 x2 (Rear HD E36 M3)
22-052810 (Left HD Strut) x1
22-052827 (Right HD Strut) x1
22-052834 (Left Sport Strut) x1
22-052841 (Right Sport Strut) x1

H&R Part Number:
29383 x1

Eibach Part Number:
2089.140 x1

Thanks to Dreamliner330 for the above list.

Vendors for Suspension parts:
Pelican Parts
ECS Tuning
Tire Rack
Your local dealer
The internet

Disclaimer: This post is simply a set of recommendations on what you do with your car. It is still up to you to make your own choice on what to buy and how to safely install these parts on your car. If performing this level of work is beyond your capabilities, please take your car to a professional who can appropriately install these parts for you. The suspension is one of the most important systems in your car and you should therefore not compromise any safety when it comes to it.

Good luck!
 
See less See more
#202 ·
My 330xi Suspension Set Up

In case other owners would like to see what the Koni adjustable sport shocks and struts with the H&R spring set up looks like...It is a rougher ride however my car has little body roll in the corners. I love this set up. I love it even more with a smooth, open mountain road!:thumbup:
 

Attachments

#203 ·
In case other owners would like to see what the Koni adjustable sport shocks and struts with the H&R spring set up looks like...It is a rougher ride however my car has little body roll in the corners. I love this set up. I love it even more with a smooth, open mountain road!:thumbup:
What size wheels and tires?
 
#206 ·
Any rubbing in the front or rear? What offset? If you know off the top of your head
 
#209 ·
The offset is +42 on the front and +45 on the rear I think? I do agree for the xi a staggered set up is not the way to go. The wheels were a graduation gift from my parents and they didnt realize the wheels were not a square set up. So I originally did 255/35/18 all around but they had to squeeze onto the front wheels. However, when I switched to the 265/35/18 and 245/40/18 they fit the wheels perfectly. The fronts didnt rub at all and the rears only grazed the inner sidewall by a hair so I filed down some on the inner wall by a few millimeters and no more rubbing.
 
#213 · (Edited)
Thanks for the quick response! That doesn't sound too bad, i really don't have much to any personal experience actually messing around with different tire sizes though...the wheels look good though!
 
#214 ·
Thank you, and they do look good and give the car a look similar to the new M3. All in all, I would prefer a square setup with a smaller diameter to regain some acceleration and reduce the weight. The set up I have looks good and handles surprisingly well, but I think it is more than the car needs.
 
#222 ·
Yeah I understand that, I didn't mean to be rude to them. I already know the pros, cons, and consequences of running the tires I am. Hence the reason why I am currently searching for a new set up. I was only trying to share my experience with my suspension set up. But thank you for your input Jason. I realize I should probably be more humble for the information I can learn through forums and other BMW owners.
 
#231 ·
I agree with GCoop (maybe I am biased I have a dog I call Coop and my name starts with G!); if Rob is gone (hope he is ok), it would be better if there was a thread detailing the parts lists, and the expectations and outcome for individuals who have experience... Otherwise they are even more blind when making decisions... I personally have to problem with the H&R/Bilstein setup and plan to replace things with poly as I dig into the suspension... but I do understand this setup may be a little harsh for some who prioritize a comfy ride over handling.

Cheers!
 
#232 ·
ya, gonna disagree.

once you go through robs phone call process you will understand, it's very involved. all the guys that go through this process are the real winners, not rob, his service is top notch and takes time. :thumbsup:
 
#233 ·
Bilstein Part Numbers:
24-024532 x2 (Rear HD E46)
24-024532 x2 (Rear HD E36 M3)
22-052810 (Left HD Strut) x1
22-052827 (Right HD Strut) x1
22-052834 (Left Sport Strut) x1
22-052841 (Right Sport Strut) x1
SamDoe1,

Regarding Bilstein struts, I found this other thread stating that if you use Bilstein HD struts with lowering springs that lower the car more than 0.75' then you are voiding your warranty.

From my understanding, bilsteins B6 line is for OEM springs, whereas the B8 line is for lowering springs. And the HDs are B6s and the Sports are B8s.

However, when looking at kits that include part numbers, and plugging in your your E46 Rear HD PN (24-024532)... it shows that as a B8 (sport) rear strut. Both kits on turnermotorsports website (the e46 HD bilstein set and the e46 sport bilstein set) have B8 struts for the rear....

this leads me to believe that there is only one rear shock offered for XI models and that is the B8 sport strut....

so would that mean that using the B8 strut on OEM non lowering springs would decrease the life of the rear strut? due to the fact it was designed for lowering springs (hence the sport and B8 name)? Or does that really only matter for the front struts considering they have both teh B6 and the B8s....

Kind of a silly question, but figured I would shoot it your way
 
#234 ·
Has anyone paired eibach springs with Bilstein sports? Would like to save some money over koni.

I know someone with hnr and bilstein and the ride was ridiculous especially the rear, the car would bounce like a civic with cut springs

Ecs tuning has ksport coilovers for 900. They have adjustable damping too. Anyone has these?
 
#236 · (Edited)
I have H&R's on my XI and the rear is not bouncy at all. In fact if you have decent shocks controlling any springs you will have no bounce. Bounce means the shock or strut is unable to effectively control the spring.

If you want to lower your XI go with Eibachs/Koni Yellows/with drop hats or Rob43's setup because it works better and is cheaper.

Eibachs/Koni Yellows/with drop hats you can expect a 14F and 13.5R (measuring from the middle of the wheel cap to the fender).
Stock XI is 15.8F and 14.6R.

Rob43's Progressive spring setup can range from being a little lower to a little higher when compared to the 14F and 13.5R numbers above this, Rob43's Linear spring setup (special rates) can go very low. He customizes it to how you use the car, hence the variations.
 
#240 · (Edited)


i"m new to car DIY, but I swapped out my suspension this past weekend. I have a 2002 325xi Wagon.. PO had Bilsteins HD in front and what looked like original OEM shocks in rear. I found both rear springs broken and one rear shock completely leaked and other in poor condition. They were both rusted beyond recognition (i have photos) ... how did this pass a safety i do not know. :facepalm:

So, I kept the HD up front, Added E36 M3 Rears with new bump stops and dropped the whole thing on Eibach springs. I kept all the original spring pads and after seeing how it sits... will likely add a 14mm rear upper spring pad to raise the rear so the spacing is closer to what's up front. I understand that because i have an Xi, the fronts do not drop very much? Am i mistaken, or can i drop the front more? I thought i messed up the fronts as they hardly moved. thoughts?

Question, do I need to worry much about camber when i've only dropped it like 1.25/.75" ? What control arms would you recommend on the rear? Do I need to get adjustable, or is stock ok with the sport height?

I do like the stiffer ride and having a level stance at wheel wells is my goal.

thanks for any help!! :thumbsup:

E.

PS.. know a body shop in Toronto that will swap out that wing for me? Case of beer? lol!!
 

Attachments

#241 · (Edited)
Hey Manny, glad you are taking care of that car; sounds like the suspension was a random assortment of worn out parts! I hope that picture is BEFORE you did your work?

I have H&R Sports from the previous owner, and recently had to upgrade my rear shocks to e46 Bilstein B8s when one of the old style B8s failed (the old fronts are still solid). I also have all poly bushings (and subframe mounts), and although I do not mind a very firm ride, I really don't think it is as bad as many on here advertise (maybe I am just used to it after years in the BMW and years in a Prelude, with similar treatment, before... the poly did make a noticeable difference). The H&Rs advertise 1.2"F/1"R drop, but as you can see in the description at FCP, it is more like 1.5-2" (I'd say closer to 1.5-1.7...?). Anyway, here the springs.

https://www.ecstuning.com/b-h-and-r-parts/sport-springs-set-sedan-models/29383/ Nice installation guide
https://www.fcpeuro.com/products/bmw-lowering-springs-325xi-330xi-h-r-sport-29383

Eibachs are less of a drop, if I recall correctly, so you definitely do not need anything for extra camber adjustment... If fact, nothing extra is needed with the H&Rs either... That being said, powerflex makes some really nice lower control arms that are a lot stronger than the stock AL ones... I upgraded mine while the suspension was being refreshed; there are some other options too, but I'd steer away (no pun intended) from the solid spherical bushings... like godspeed... Here is a link to the powerflex rear LCAs... They are pretty sweet, even if the car is so low that I never see them!

https://www.ecstuning.com/b-powerfl...le-rear-lower-control-arm-kit/pfr5-4615g~pfx/

Finally, regarding upper spring pads... Your 02 (post 9/01) should have the thicker 14.5mm pads, rather than the 5mm pads. Personally, I upgraded my rear upper pads to superpro poly (I chatted ECS and I think they said they are 11mm), which raised my rear up just a bit. I never thought it looked too out of level in the first place (lower in rear), but it certainly looks fairly level now... Here are the pads... When I looked at prices for new genuine pads I saw no reason not to go poly...

https://www.ecstuning.com/b-superpro-parts/spring-insulator-upper-bushing/spf135810k~spr/

Cheers!

edit: here are some good threads on xi suspension... and oh yeah, lowered xis do eat front axles, so, if you can get some with a lifetime warranty, like FCP, I recommend it!

http://forum.e46fanatics.com/showthread.php?t=731343

http://forum.e46fanatics.com/showthread.php?t=1088219

http://forum.e46fanatics.com/showthread.php?t=902345 (post with links to more threads...)
 
#242 ·
Hey Manny, glad you are taking care of that car; sounds like the suspension was a random assortment of worn out parts! I hope that picture is BEFORE you did your work?

Unfortunately.. no, that picture was taking the day after. I've since put 500 km on the car doing a road trip out to Prince Edward County over the long weekend. While driving around the country roads to visit the wineries, I hit a pot hole and now have a "clunk" in the front. Upon immediate inspection, no moving parts.. then i pulled the right front wheel off and noticed some play in the hub. Bearing?

Also while there i noticed this... the springs that were compressed by my mechanic where not done the same. They spring itself does not seem to be seated in the appropriate location. ..please see images. Do these look right? I was thinking of going back to him to have them adjusted as i do not have the appropriate tools.




Could that be the reason the front is sitting higher? :facepalm:

oh, and since its been a week I check my strut mount bolts and they needed a few turns.

So, I"m still thinking raising the rear with spring pads and taking the front struts back to mechanic to have them properly aligned.

Thoughts?
E.
 

Attachments

#245 · (Edited)
I agree with Mariner; it sounds like they should rectify the spring situation and realign at no cost, assuming you paid for an alignment already.

i pulled the right front wheel off and noticed some play in the hub. Bearing?
If you have the car up, with the wheel on, see if there seems to be play... could be the balljoint(s) on the control arm... How do the boots look?

Is it possible the front is riding high because of the original shock bumper is too tall with a lowering spring? Was thinking of cutting 1" out of them? (Shocks are Bilstein HD on Eibach Springs)

Also, noticed my rear is not level and one side is tucked in more than the other. The right side is lower by a full inch compare to left side. I just ordered spring pads, Im hoping new pads will help. Also, oddly the right wheel is also almost 1 inch closer to the center of car than the left side (meaning, left side, wheel is closer to fender and right is further away. I was thinking of adding a spacer to widen the rear.. and noticed that only the right side was tucked in. I'm going to take it apart and measure part for thickness to see where this illusive 1" has disappeared or appeared (on left side).
I would contact Eibach about cutting the stops... I think the PO of my car said the H&Rs came with directions to cut some off the front stops... You might be able to find that info on this site.

That stuff about the rear seems wonky since you just did work back there and I assume everything looked okay... If everything is right you should obviously not need a spacer and that sounds concerning! Not sure what you tell you other than good luck!
 
#243 ·
upon further inspection.. knocking noise was loose front stabilizer that got knocked loose when i hit that pot hole. :facepalm: it is now fixed.

Is it possible the front is riding high because of the original shock bumper is too tall with a lowering spring? Was thinking of cutting 1" out of them? (Shocks are Bilstein HD on Eibach Springs)

Also, noticed my rear is not level and one side is tucked in more than the other. The right side is lower by a full inch compare to left side. I just ordered spring pads, Im hoping new pads will help. Also, oddly the right wheel is also almost 1 inch closer to the center of car than the left side (meaning, left side, wheel is closer to fender and right is further away. I was thinking of adding a spacer to widen the rear.. and noticed that only the right side was tucked in. I'm going to take it apart and measure part for thickness to see where this illusive 1" has disappeared or appeared (on left side).

Thoughts? :bow:

E.
 
#244 ·
Of your photos, the 2nd one is not correct. Is the second photo the one that broke the sway bar link ? A breaking link MIGHT have twisted the spring on its pad.

When the rotation of the spring pad is correct relative to the end of the spring it is just about like photo #1.

Of course it seems wrong, because the end of the spring is at the edge of the "cliff", not seated in a "pocket" of the spring pad like many other manufacturers do. You can find more information in Bentley and searching some other threads on this. It is non-intuitive enough that in recent work on my car I took a look, began to fret over the rotation, and then remembered I was looking at my 325xi, and all was okay. BUT mine are rotated the same on both sides - looks to me like your second one slipped as the spring compressor was released.

The xi's sit with front end "too high" when assembled correctly in stock configuration - leading many to slightly lower their front suspension. But this gives up some clearance and travel and may wear the front axles more quickly.

So you do want your shop to reposition your spring. Maybe your shop will re-set the spring and redo your alignment as good will for free.

Mariner05
 
#248 ·
Glad you got it mostly sorted, and haha about the dealer/wheels... If it drives good who gives a damn if it is hunkered down a little in the back!? Just put a snow plow on the front and it should even it out <img src="http://s1.E46Fanatics.com/forum/images/smilies/wink.gif" border="0" alt="" title="Wink" class="inlineimg" /> . That is a good looking wagon regardless. Cheers!

Thanks guys.. ya we have plenty of snow here! I may get koni yellows for front..but this constant mention of quickly worn front axels from lowering the front any more does concern me. Don't want that!

Ya.. i like the car! Only 105 miles on it. But its got some cosmetic issues..needs front dirvers wing replaced and 5 rust spots fixed. Thinking of painting whole car as i see another 5 year in it. If you spread the cost of a paint job over 5 years, it seems to make sense.

As i once heard someone say, If you don't look back at your car after you park it, you don't want to be driving that car. ***x1f600;
 
Top