Suspension Refresh Guide. Information w/ complete parts list.

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)

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.

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

http://tis.spaghetticoder.org/s/view.pl?1/06/73/30

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)

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
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!)

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. http://www.oembimmerparts.com/produc...26758623my.htm

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 which can be found on eBay. http://www.glowcor.com/ViewCatalog.asp?ID=132

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)

This will need a lot of editing, clarification, and possibly corrections. It's late now so here's what I have for now.

You rock man.

Originally Posted by trive2

You rock man.

Agreed , thanks for this

No problem, my brothers. I have stage 3 on my list of to do later this year. If anybody has access to the special tools required or is renting them out, let me know.

Great resource, Good attention to Detail Mango !

Thanks for the consolidated info.
Great write-up

Stage 3 is in my near future.

For posterity, I was wondering if there is a typo in:
Stage 1 (Struts and Shocks)
Where you provide the right side part number for part described as "Strut Suspension". I'm guessing its supposed to read Sport Suspension.

Originally Posted by ///MPR77

Thanks for the consolidated info.
Great write-up

Stage 3 is in my near future.

For posterity, I was wondering if there is a typo in:
Stage 1 (Struts and Shocks)
Where you provide the right side part number for part described as "Strut Suspension". I'm guessing its supposed to read Sport Suspension.

Thanks. Probably lol. I'll change it. I'll blame this one on the beer...

I'm sure there's lots of typos and inconsistencies. Let me know whatever you guys find.

Stage 1, 2, and 3 recently completed. Now I just need to get the manual tranny in.

I'd put tie rods in Stage one though. They are cheap/easy and you really don't want those failing.

Originally Posted by cposk

Stage 1, 2, and 3 recently completed. Now I just need to get the manual tranny in.

I'd put tie rods in Stage one though. They are cheap/easy and you really don't want those failing.

I agree but I'm keeping people's budgets in mind. People are complaining that I'm overly anal about replacing things so I give the people what they want. LOL

It's just a guide and not a be-all, end-all rule book. Feel free to mix and match whatever you want without any problems coming up.

Congrats on doing 3. I need a GOOD day or two to complete this as well as the time, space, and tools. For now though, everything looks and feels great. I'm in no rush.

Originally Posted by E46Mango

I agree but I'm keeping people's budgets in mind. People are complaining that I'm overly anal about replacing things so I give the people what they want. LOL

It's just a guide and not a be-all, end-all rule book. Feel free to mix and match whatever you want without any problems coming up.

Congrats on doing 3. I need a GOOD day or two to complete this as well as the time, space, and tools. For now though, everything looks and feels great. I'm in no rush.

I even did the TMS rear subframe reinforcement (stage 4???), haha. But I'm like you, I try to fix one thing and end up replacing half of the car. My wallet hates me.

Originally Posted by cposk

I even did the TMS rear subframe reinforcement (stage 4???), haha. But I'm like you, I try to fix one thing and end up replacing half of the car. My wallet hates me.

you're right I should probably add the TMS plates. Don't they make swaybar reinforcement plates too for the mounting areas?

And yes... i know what you mean. but driving the car is such a joy it's worth it.

Originally Posted by E46Mango

you're right I should probably add the TMS plates. Don't they make swaybar reinforcement plates too for the mounting areas?

And yes... i know what you mean. but driving the car is such a joy it's worth it.

Yes and a front subframe reinforcement kit.

Thank you very much!!

thanks...so the ZHP struts are different from the sports suspension? Please update

Updated to reflect ZHP part numbers. The part numbers I posted as sport were actually ZHP. So I had to find sport part numbers. There's so many part numbers for shocks/struts, its confusing. But I checked w/ realoem and I think i have it down. Let me know if anything else needs changing.

I know there's TWO types of springs (sport and ZHP sharing their own) and non-sport having their own. But are there three struts/shocks types? non-sport, sport, and zhp? or only non-ZHP and ZHP?

Originally Posted by E46Mango

Updated to reflect ZHP part numbers. The part numbers I posted as sport were actually ZHP. So I had to find sport part numbers. There's so many part numbers for shocks/struts, its confusing. But I checked w/ realoem and I think i have it down. Let me know if anything else needs changing.

I know there's TWO types of springs (sport and ZHP sharing their own) and non-sport having their own. But are there three struts/shocks types? non-sport, sport, and zhp? or only non-ZHP and ZHP?

all i know is that while shopping for these items, there's usually just a sport or non-sport option aside from aftermarket...

Great thread, and very pertinent info to have. Thanks for the part numbers...i'll be needing some of these by the end of the season.


If it helps...some additional things you may want to mention:

Install tips for sway bar end links
-Front sway bar endlinks require a very thin 16mm box end wrench to hold the ball joint shaft from behind without damaging the boot.

Install tips for front lower control arms
-The ball joints have a tendency to spin when tightening the locking nuts down for the first time. Put a jack under the ball joint and jack it up to put some pressure on the ball joint from below. This will keep the shaft from spinning and allow you to tighten the nut down easily.

Install tips for struts
-The spindle will have nothing to support it when you have removed the strut. There is an easy way to keep it in place so you don't damage the outer ball joint by letting it flop around. Thread one of your wheel lug bolts into the hub and turn the rotor so the bolt is at the 12:00 position. Put a jack stand by the rotor and extend it up so it's under the lug bolt. Let the lug bolt rest on the top pf the jack stand. This will support the spindle safely.

Originally Posted by fiveightandten

Great thread, and very pertinent info to have. Thanks for the part numbers...i'll be needing some of these by the end of the season.


If it helps...some additional things you may want to mention:

Install tips for sway bar end links
-Front sway bar endlinks require a very thin 16mm box end wrench to hold the ball joint shaft from behind without damaging the boot.

Install tips for front lower control arms
-The ball joints have a tendency to spin when tightening the locking nuts down for the first time. Put a jack under the ball joint and jack it up to put some pressure on the ball joint from below. This will keep the shaft from spinning and allow you to tighten the nut down easily.

Install tips for struts
-The spindle will have nothing to support it when you have removed the strut. There is an easy way to keep it in place so you don't damage the outer ball joint by letting it flop around. Thread one of your wheel lug bolts into the hub and turn the rotor so the bolt is at the 12:00 position. Put a jack stand by the rotor and extend it up so it's under the lug bolt. Let the lug bolt rest on the top pf the jack stand. This will support the spindle safely.

Good tips but I never understood why people always say you need a special thin wrench. Every generic 16mm wrench I've ever used (with the exception of one chinese autozone brand which stripped) worked perfectly. Just your run of the mill plain old thick 16mm wrench. Always fits just fine.

Dis is a good thread

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.

I have this clunk/pop when I driving over a bump or dip. What exactly is the issue here...?

I know its not anything else on the suspension because we replaced all the key parts. What you are describing sounds exactly like my car.