E46 Fanatics Forum banner

Suspension Refresh Guide. Information w/ complete parts list.

226K views 274 replies 103 participants last post by  hiddenbunny 
#1 ·
This guide will provide essential information and part numbers to refresh your non-M E46 suspension. I realize a lot of people are on budgets, so I'll divide this list into three stages in order of most important (failure prone) to least important (more durable).

Stage 1:

Front control arm bushings w/ bracket, part number 31126783376 x 2

Associated hardware:

Bracket bolts (four per car), part number 33306760652 x4 (Meyle HD units come w/ new bolts. If Genuine BMW does too, then no need to order new bolts for the brackets) BMW bushings are great and they maintain the supple yet firm steering feel BMWs are known for. You can take it a step further in both feedback/feel and durability and get a solid rubber design like Meyle HD.

At 50,000+ miles, these bushings are well on their way out, if not completely expired. Symptoms can and will include play in steering at any speed, click/clunk as you sharply apply the brake, or steering wheel vibration under braking or general looseness in the steering.

Install tips:

If you're replacing just the bushings, you'll need a gear puller to separate the bushing and bracket from the end of the control arm. To reinstall, lube up the control arm and bushing with 1 part soap to 20 parts water and firmly tap onto the arm with a rubber mallet. The end of the control arm should be flush with the end of the bushing. Don't tap on too far and don't tap on too little. When you reinstall the reinforcement plate, make sure you purchase 8 new bolts. These are designed to be changed every time you reinstall the plate. They shear in the event of a crash. You don't want to compromise these very crucial items.

Reinforcement plate bolts:
Part number 31106772199 x8

Resources:

http://www.understeer.com/lcab.shtml

Struts and Shocks

Struts are in front, shocks are in back. If you have 50,000 or more miles on your E46, your Original Equipment (OE) Sachs-Boge Struts and Shocks are severely degraded, if not totally blown out. You won't notice this because your BMW is stiffly sprung and sway-barred. It will still ride firm, turn sharply, etc. The struts/shocks are crucial in wheel control. Your directional stability is severely compromised when your struts and shocks are failed. This will also cause excess and uneven tire wear. The parts listed below are OE Sport Suspension units. (I'll probably edit this list to include ZHP as well) Keep in mind these part numbers are for OE/OEM units. Many people, including myself, go aftermarket. Personally I went with Bilstein.

BMW performance ZHP, Strut left, part number 31312282459
BMW performance ZHP, Strut right, part number 31312282460

Sport suspension 9/01+ Strut left, part number 31316750791
Sport suspension 9/01+ right, part number 31316750792

Associated hardware

Strut mount (2 per car), part number 31336752735
Bump stop (2 per car), part number 31306757046

Again, these are for stock replacements. Some people go aftermarket as the firmer shocks tend to eat at and destroy the stock design as it is too flimsy. I went with Rogue Engineering.

Strut tower reinforcement plates (VITAL--must install!) two per car, part number 51717036781

Shocks

Shocks BMW performance ZHP, (2 per car) part number 33522282461
Shocks sport package, (2 per car) part number 33521096366
Shock mount (2 per car), part number 33521092362

Associated hardware

Bump stop (2 per car), part number 33506757047
Paper gasket (2 per car), part number 33526772864
Shock tower reinforcement plates (2 per car), part number 51718413359 (VITAL--must install!)

If your bump stops are in good condition, you may reuse. If soft, deteriorated, or chunks missing just replace it. If you go aftermarket Bilstein, they feature internal bump stops. No need for external bump stops.

Install tips:

Perform this work at your own risk. Do not engage in any work that is beyond your comfort and/or skill level. Always secure car on level ground using quality jackstands. Use quality jacks to lift car only, not support.

You will need a quality set of spring compressors, a variety of heavy-duty tools such as a breaker bar, heavy duty ratchet, large socket set and an allen key set (I believe you'll need a 6mm allen key to prevent the strut piston from turning as you undo the top nut.) You'll need a 21 or 22mm socket to undo the top nut. Make sure the socket has a hexed-head on it so you can turn it using a 21 or 22mm open end wrench as you hold the piston stationary using a 6mm allen key. This is self-explanatory as you begin to do the work. A nice electric or air-powered impact gun can also do the job quite nicely.

For installation and torque specifics, consult TIS or a Bentley owners' manual.

Always reuse all washers in correct orientation.

Always replace suspension components in pairs.

Always replace any hardware that is severely corroded or otherwise compromised or damaged.

Always install quality name-brand parts.

Front swaybar endlinks

Chances are your front swaybar endlinks are torn where the rubber boots hold the grease at the balljoints. Replace. Part number 31356780847 (2 per car).

Rear swaybar endlinks

These are typically solid and last a lifetime. Part number 33551094619 (2 per car)

Install tips:

Both front wheels have to be unloaded before you begin to remove/install these. Use one 16mm socket and ratchet and a 16mm open-ended wrench on the other side to counter hold the bolt as you loosen the nut. No special tools are needed. These need to be installed TIGHTLY or you WILL hear a clunk or pop while driving over bumps. I can't stress this enough.

Front swaybar bushings

These definitely need replacing. Worn bushings will compromise the response and stability of side-to-side maneuvering. Two per car:

23.5mm for 4/01+ vehicles with sport package, part number 33556751269

23mm (non-sport?) part number 31351097179.

Note: I ordered 23.5mm bushings but received 23mm bushings. I installed them without any problems. Slightly tighter fit.

Rear swaybar bushings

Rear: 18mm all sedans 4/01+, non-sport sedans up to 4/01, part number: 33551138104

19mm all sedans with sport suspension up to 4/01, part number: 33551094551

20mm for convertibles, people who have upgraded, and I believe XIs, part number 33551096669

Bonus: 20mm rear swaybar part number 33556751267

Stage 2

Control arms


Theres an inner and outer balljoint. Typically the outer balljoint fails first and is encased in nylon (less durable) on non-M and non-ZHP models. It is recommended to replace with ///M ZHP arms or Meyle HD arms.

Control arm left, part number 31126777851

Control arm right, part number 31126777852

Or you can just order the Meyle HD set with brackets, bushings, and new bolts. BMW E46 3-Series Control Arm Kit By Meyle HD 31122343352 & 31122343353

Install tips:

Front of car on jackstands, medium and large pickle forks, plenty of extensions, wobbles, step-down adapters. Access drivers side control arm inner nut from top and passenger side from down below.

Always buy brand new genuine BMW nuts for the control arms (two per arm) part number, 31106774714 x2, and 32216769539 x2. Do not skimp on these. Do not use the ones supplied by Meyle.

Tierods (complete assembly)

Self-explanatory. Any signs of play, damage or leaking of rubber balljoint casing, replace.

Tierod left part number 32211096897
Tierod right part number 32211096898

Tierood boot kit
Two per vehicle, part number 32131096910

Rear trailing arm bushing:

Replace these at 60,000+ miles. Worn bushings will degrade rear-end stability and basically cause your rear wheels to excessively and unexpectedly to steer. You'll notice this especially when accelerating from a stop.

Part number 33326770817 (two per vehicle)

Install tips:

Use MIS RTAB tool. Nothing else. Don't even think about it or attempt it. Use large hose clamp in center of bushing to completely compress the split joint as you begin to press it into the trailing arm. Once in, remove clamp.

Be sure to unclip/unscrew main brake line and associated lines clipped onto the trailing arm. Have heavy duty breaker bar and torque wrench ready with two 18mm sockets. Pre-load bushing carrier by aligning the same way it came out. For me the carrier was lined up PERFECTLY with a line naturally casted into the trailing arm. You'll see what I mean when you eyeball it. Worked like magic.

Get an alignment immediately after. Your toe will be WAY out of spec no matter how much you try to get it lined up perfectly.

Steering Coupler/Flex-Disc/Universal Joint

Part number 32301094703. Apply blue loc-tite when reinstalling the bolts. Make sure threads are cleaned on all bolts and the two splined shafts which the coupler installs on.

Install tips:

Do this part at the same time as the control arm bushings. The reinforcement plate will have to come off.

Stage 3

These require tons of labor and special tools. These are for the pickiest of picky. You'll need an E36/E46 rear axle service kit. Check out my page The Ultimate E46 tool guide for complete list of tools which includes the rear axle kit: http://www.e46mango.com/2016/10/the-ultimate-e46-tool-guide.html

Rear end subframe and rear upper/lower, inner/outer control arms bushings and balljoints.

Rear control arms/trailing arm
(except main RTAB because it's listed under stage 2)

33326775551 x2
33326771828 x2
33321092247 x2
33326770824 x2

Subframe:

33316770783 x1
33316770784 x1
33316770781 x2

Differential:

33176770788 x2
33176751808 x1

Differential Bushing Bolts:

33176760337 x2 (Two small diff bolts)
33176760336 x1 (One large diff bolt)
33306760349 x1 (Self-locking nut for large diff bolt)
 
See less See more
#99 ·
Mango, I've got a whole list of suspension parts to do on my 323i. Tell me what you think:



Also, what do you recommend for springs? I've been thinking about using OEM, but I wouldn't mind something slightly lower for a better look. Thinking H&R or Eibach. I still have to add the rear shock reinforcement plates and the strut reinforcement plates as well. For some reason when I type the part numbers in they don't show up on the website there.
 
#100 ·
Looks like I would need a shock/strut combo that accepts lowering springs, and the Bilstein Touring isn't one of them. I'll stick with my current springs. Going to be ordering all of this pretty soon. Looking forward to getting it on my car.
 
#109 ·
#112 · (Edited)
In your original post, you mention that one should get an alignment after doing the RTABs... but what about for other bits?

Do you recommend getting an alignment after doing the CONTROL ARM BUSHINGS only?

After replacing struts/springs?

After ANY suspension adjustments/replacements?

(Could get expensive unless you do everything at once, but just curious as to the consensus on this.)
 
#114 ·
CABs=yes. Camber can change and as a result, toe could be affected.

RTABs=yes.

Struts=likely not affected but by removing the strut body, you can possibly change the camber slightly.

Springs=yes especially if different height.

Do as many components as you can together at one time. your car may/may not feel fine after getting the above components done, but unless you get it on a rack, you'll never know for sure. your tires will tell you though after some time
 
#113 · (Edited)
correction on front strut mount p/n

Associated hardware

Strut mount (2 per car), part number 31336752735
Regarding the front strut mounts (also called guide supports), the part number quoted above is for certain E39 and X3 models.

Per realoem, these days it appears BMW sells a kit which includes 5 different pieces, including the mount itself. Diagram below indicates part number for the kit you need depends on whether your E46 was built prior to November, 2003. But then again the "early" part number doesn't seem valid and or available.

If anyone knows if the "later" number can be used on <11/2003 build dates, do tell.

Note there is also apparently a core charge, so save your old parts.

 
#119 ·
Hi all, I've got a 2001 325i with 185k and the sport suspension (or what's left of it, ha). I'm in desperate need of a suspension refresh. I've got a couple of additional questions on this incredibly useful thread.

1: I drive a lot in snow & rough roads - I live in Seattle but I ski almost 100 days a year, camp, etc. I am considering the Bilstein B12 kit (sport, with eibach prokit springs). Would the adjustment in ride height negatively impact my "offroad" activities much?
2: For such a non-stock strut and shock kit, such as the bilstein kit, are the bump stops necessary?

Thanks again - this forum has already saved me thousands of dollars. :)
 
#120 · (Edited)
Thanks for this thread. Still need some advice:

I have replaced my front control arms + bushings, tie rods and sway bar links. Still my e46 is very unstable at bulky roads, steering wheel pulls towards left / right creating dangerous situations.

The front struts seem a little bit rusted, could this be the issue of an unstable e46? My car has 110,000 miles and dont know if they recently been replaced. Hope someone can help me on this.
 
#121 · (Edited)
Simple rear suspension overview

I made a simple MS paint illustration showing the *rough* locations of all rubber-mounted bushings and/or balljoints that need addressing as you near 150k miles. I'm beginning my stage 3. I already have four balljoints ready to go in this weekend and my differential bushings as well. Even though I have part#s listed on my page, this was really messing with my mind so I had to do additional "research" to make sure #s are correct. Some of the #s are out of order but this will give you a rough idea.

Mod, please feel free to move it to the first page under rear suspension.

 

Attachments

#130 · (Edited)
Mr. Mango, this thread has pretty much everything I was looking for. Thank you! :thumbup:
Killer thread. I had this saved in my repair section for a while now. I finally got some cash to do everything on the list including a sport cup H&R shocks and springs set.
Great post, thoroughly enjoyed it all.
I just wanted to say thank you for putting this thread together. It was a great reference point as I got all my suspension parts together.
Thanks for this thread.
I just wanted to say thank you for putting this thread together. It was a great reference point as I got all my suspension parts together.
Sweet thanks.
you're welcome :)
 
#127 ·
Great post, thoroughly enjoyed it all. Let me start by saying I recently bought a 2001 325i, an E46 I come to find out. I also found out I need to change the worn out front suspension.(119K) It has the sport suspension. Automatic, so my wife can drive it but that's another story. My son, who has access to a lift, had it up on said lift today and we've decided to change it all, control arms...probably Meyle(where can you get the ZF stuff?),inner/outer tie rods, sway bar links...

The one thing I haven't read here, and it's most likely somewhere here, is ...I want to change the struts and shocks. What struts do I get that will be compatible with sport suspension springs? I just read that springs do get soft over time so should I replace those too or leave them? Thanks for any and all input.
 
#128 ·
clarification on suspension (shocks/struts) only

Mango, If I just follow your list for the suspension parts (shocks/structs) do I need to buy any other parts? i.e. do I need one of the pre assembled kits? I am looking to order all through ECS and just looking for the basic replacements, but to also do a complete job as I only plan on doing this once (or maybe twice in another 80K miles).
 
#131 ·
Just wondering, I was gonna start out replacing the front control arm bushings, does anyone know anything about the brand MTC? I know usually UUC is the way to go but they're almost 3 times the price of the MTC ones on ecs and unless it's actually worth it, I'm not spending $200+ on bushings..
bushings in question: http://www.ecstuning.com/Search/31126783376/ES1899439/
 
Top