Help with Suspension Refresh at 50k miles/10 years

NOTE: for those looking to find my final parts list, scroll down a bit through this first post.

I'm really new to suspension work and am a little overwhelmed with the loads of information and options available so I'm hoping someone can help me narrow down some things or at least point me in the right direction. Later this summer I plan to swap out my original shocks and struts for Koni Yellows (Sport). The original shocks and struts have only 50k miles on them but they've been on there for 10 years and it seems that a fair number of people believe that the original Sachs shocks/struts are only good for 40-50k miles so I'm guessing they're due to be changed anyways. My current plan:

• Koni Yellow (Sport) shocks and struts (on sale for $498 from Race Consulting Agency)
• Keep using the original springs
• BMW Strut tower reinforcement plates (part no. 51717036781)
• Rogue Engineering Rear Shock Mounts (http://www.rogueengineering.com/rogue/S_BUSH/RSM.html)

Now for the questions! First, since I'm only at 50k miles but 10 years on original equipment, I'm not sure what else I should replace while I'm doing the above parts. Should I assume I should also replace the following:

• Strut mounts
• Front and rear bump stops
• Upper and lower spring pads
• Dust boots (do these come with the Konis)?

If so, are there specific brands I should look for, or is OEM sufficient? Is there anything I am missing? I plan to do various bushings later and will post back here with questions about those.

My other question is about the Koni shocks. Currently a whole set can be had for $498 shipped from Race Consulting Agency thanks to a tip from FlyRide here. However, I have had my eye on TC Kline's modified Koni shocks (link: http://www.tcklineracing.com/webdocs.../Details30.cfm) that are externally adjustable like Koni's standard front struts but they're 2.7x more expensive than the normal Koni rear shocks. So my questions are:

• Are there other brands that modify Koni Yellows like TC Kline? I remember people talking about Ground Control but they don't seem to carry modified Konis other than full coilover kits.
• If the TC Kline shock fails/breaks, can they be repaired under Koni's warranty?
• Do I have to cut up my trunk liner/carpet to get the TC Kline shocks to fit?

$264 for the TC Kline vs $98 is a large premium to pay for rear shocks, one I would only consider if I don't have to cut up my trunk carpet/liner and knew that if the shocks failed they could be repaired/replaced by Koni.

All that said any info or suggestions would be greatly appreciated!

EDIT:
For those not wanting to wade through the pages of responses, below is the finalized list of parts that I ended up using for a relatively stock suspension refresh:

• Koni Sport (Yellows) struts (8741-1390RSPORT [front right], 8741-1390LSPORT [front left]) and shocks [2x 8040-1271SPORT])
• Rogue Engineering rear shock mounts (RSM) (no part number)
• Strut tower reinforcement plates (2x) (51717036781)
• Front strut mount (2x) (31336752735) (FCP Euro)
• Front spring pads (2x) (Upper: 31331091867, Lower: 31331096664)
• Rear spring pads (2x) (Upper: 33531136385, Lower: 33531094518)
• Bump stops (2x) (Front: 31306757046, Rear: 33506757047)
• Dust boots (2x) (Front: 31331094749, Rear: 33521136283)
• Z4M Front Control Arm Bushing (FCAB) (Left: 31107836862, Right: 31107836863)
• Z4M Rear Trailing Arm Bushing (RTAB) (2x) (33326770817)
• Hex bolt w/ washer for FCABs (4x) (33306760652)
• Locking nuts for strut mounts (6x) (31316769731)

Total cost (purchased June 2015): $1,002.78. Cost broken down by part can be found here

Notes:

• This list assumes you reuse your stock ZHP springs
• If you want a top-adjustable Koni Sport rear shock, you can use the ones meant for the Porsche 911 (part no. 82101159SPORT). This means the shocks won't have to be removed to be adjusted. I'm not 100% if any modifications are necessary to get the shock to fit or not.
• I chose Z4M front control arm bushings (FCABs) because they are solid rubber so they should last longer, and offer slightly increased caster (slight increase in straight-line stability, slight increased turn-in effort). Many members here have them and like them and have had no issues other than the aesthetic "issue" of the front wheels being pushed slightly forward in the wheel well.
• The strut mounts I purchased were by Lemförder because they were far cheaper than BMW Original and Dane vouched for their build quality.
• As far as I know the hex bolts (33306760652) and locking nuts (31316769731) are not strictly necessary. You can (I think) just use Loctite on the hex bolts and just reuse the locking nuts. I chose to get both since they were relatively cheap (~$15 total) and one of those "while you're in there" sort of things.
• According to the guide by Mango on E46Fanatics about suspension refresh items (link:http://forum.e46fanatics.com/showthread.php?t=932561), you should replace the reinforcement plate bolts (8x 31106772199). I opted not to, but definitely something to consider. On the whole the guide was very helpful.
• I opted to not do the rear trailing arm bushings (RTABs) with this refresh until I hear back from Peter (username: slater) with his opinions on the Bimmerworld sealed spherical RTABs he purchased. If not those, then I plan to purchase OEM M3 or Z4M RTABs with limiters, probably from Vorshlag (link: http://www.vorshlag.com/product_info...roducts_id=515). EDIT: I ended up not waiting on slater (Peter) and purchased the Z4M RTABs (part no. 33326770817) with Vorshlag limiters. I have had no issues and like them so far.
• Bimmerworld sealed spherical RTABs: if you jump to post #56 there's a pretty lengthy discussion about them compared to rubber and poly RTABs. Pictures of the spherical RTABs can be found here The spherical RTABs can be purchased here.
• I originally had the rear bump stops as 33531138109 but those are supposedly for lowered suspensions which is not the case for me since I will be reusing my stock ZHP springs.
• I did not include or replace the "upper spring pocket with spacer" (item 7, here: http://www.realoem.com/bmw/enUS/show...diagId=31_0408, part no. 31326769667) because no one mentioned I should nor did it seem necessary.
• Install notes can be found in my project thread here for the rear shocks and here for the front struts

Additional parts for a suspension refresh to consider:
Note: I have not purchased nor installed these parts, but they are the likely parts I would use if I were to replace these parts.

• Front sway bar end links (2x) (31356780847)
• Rear sway bar end links (2x) (33551094619)
• Front sway bar bushing (2x) (33556751269)
• Rear sway bar bushing (2x) (33551138104)
• M3 Rear outer upper and lower ball joints (4x) (33306852895)
• Front control arms (there is some confusion on part numbers: Link)

Additional Links:

• My thread discussing alternative wheel options
• My thread on maintenance spreadsheets and available templates

EDIT 2: 09/21/2015
I now have everything installed and had an alignment done (FCABs and RTABs w/ limiters installed by an indy). I used Shawn's (username: ELCID86) and Daniel's (username: NoVAphotog) previous alignment numbers to get a rough estimate of where they should be. Initial thoughts are the car feels great! The nose wants to dive into corners, the rear feels very planted when you step on the throttle out of the bends, and it feels very stable in a straight line at high speed. I would highly suggest this setup for anyone wanting to keep their car's ride comfortable but still agile. For a little more of a review on the feel of the car post-refresh and some installation advice, click here.

For those worried about the look of added caster from the Z4M FCABs, below is what my car looks like with them. You will notice the wheel sits ever so slightly forward in the wheel well but you can barely notice it. It doesn't bother me and I like things to match up and be symmetrical.

http://i.imgur.com/yNoEoWu.jpg

Just ordered (minutes ago) a set of Koni FSDs for the ZHP. I put the Koni Sports ('yellows') on my 330Ci last year and I really like them, but want to try the FSDs this time around. I'm of the opinion that you should definitely change the strut mounts and bump stops...you don't want to have to take it all apart again if one of those fails after installing the new struts! I also think the reinforcement plates are a good idea - did them all the way around on the Ci and will do the same with the ZHP. The Rogue Engineering mounts are nice, but pricey...can't decide if I want to go there. Koni struts do NOT come with dust boots, so not a bad idea to buy new ones. I think I'll replace the spring pads this time around. I didn't on the other car and don't think it's the end of the world, but I do kinda wish I had done it. As far as brands for things like strut mounts, I've had good luck with Meyle...

Hmm...I'm leaning that I should replace all those ancillary parts (second list) as well so I have peace of mind. You like Meyle? Any reason why them over BMW OEM for the ancillary parts?

Thoughts on the Koni Adjustable Rear Shock from Dinan (link: http://www.dinancars.com/product/d14...-series-e46-2/) as a far cheaper alternative to the TC Kline or the standard Koni Yellows? Seems like a perfectly good option compared to the TC Kline. Even if the valving is different, would it matter much between these in the rear and regular Koni Yellows in the front?

Do you plan to replace the shocks again in 50k? You could probably just replace the shocks/struts and add the reinforcement plates to the front. Then at 100k due a complete overhaul again.

OR

Do the Koni Yellows for $498, new upper and lower spring pads for the front and rear, rear shock mounts, rear shock mount gaskets, upper front reinforcement plates and strut mounts, and dust boots with bumpstops. And not have to worry about it for another 100k.

What are your plans for how you will use the car?

Quote:

---

Originally Posted by Vas

Do you plan to replace the shocks again in 50k? You could probably just replace the shocks/struts and add the reinforcement plates to the front. Then at 100k due a complete overhaul again.

OR

Do the Koni Yellows for $498, new upper and lower spring pads for the front and rear, rear shock mounts, rear shock mount gaskets, upper front reinforcement plates and strut mounts, and dust boots with bumpstops. And not have to worry about it for another 100k.

---

Vas,

I think I'm leaning toward your second option. I'd rather just replace it all and have peace of mind since those parts aren't too expensive in the scheme of things. I'm just trying to figure out:

1. Do I have all the necessary parts listed for a refresh (not including bushings that I'll do later) and what brands I should use for those ancillary parts?
2. I'm not sure if it's a smart idea to get the TC Kline or Dinan rear shocks that are externally adjustable because I can't tell if they're covered by Koni's normal warranty since they are modified by these third parties. Also, if either the Dinan or the TC Kline shock is revalved, I don't know how that will affect handling with stock Koni Yellows up front i.e. can the externally adjustable rear shocks by these companies be adjusted to have similar rebound as the regular Koni front struts?

Follow up question that you raised, Rogue Engineering lists their rear shock mounts as coming with the following:

• Two (2) Rogue Engineering 6061-T6 CNC, Anodized Rear Shock Mounts
• Four (4) Shore A 60 Rubber Bushings (stiffer TRACK versions available at extra cost)
• Two (2) 303 Stainless Steel Bushing Spacers (to be used with standard 10mm rear shocks, remove these for 12mm)
• Four (4) 303 Stainless Steel Washers (2 required per mount)
• Four (4) Yellow Zinc plated M8 serrated lock nuts
• Two (2) Shock Tower Reinforcement Assemblies (with 10.9 hardware welded)
• Two (2) factory gaskets

In your second list you mentioned "rear shock mount gaskets," which I didn't have in my list. From the Rogue Engineering list above, it says "two (2) factory gaskets," I assume those are the same (bolded above)? I just want to make sure that if I got the Rogue Engineering RSMs I shouldn't order separate gaskets.

Thanks for all your help!

EDIT:

Quote:

---

Originally Posted by Hermes

What are your plans for how you will use the car?

---

I plan to use it for pretty much street use only with maybe 1-2 driving events a year max. A friend's step father is a driving instructor at Portland International Raceway and he's always offered to take me out there on open track days so I'm finally hoping to take him up on his offers.

on top of what vas said for his 'second option', i'd add in RTABs and FCABs if you haven't replaced them yet. also, you might not need to replace the front strut mounts, they seem pretty robust.

peter

Quote:

---

Originally Posted by slater

on top of what vas said for his 'second option', i'd add in RTABs and FCABs if you haven't replaced them yet. also, you might not need to replace the front strut mounts, they seem pretty robust.

peter

---

Exactly the info I'm looking for, I hear so much differing info when I try and look over suspension parts through Google. I trust you guys a lot more. Thanks!

Also, I hear a lot about RTAB limiters. Is that something I need or is it more for a non-street application?

Quote:

---

Originally Posted by BMWCurves

Exactly the info I'm looking for, I hear so much differing info when I try and look over suspension parts through Google. I trust you guys a lot more. Thanks!

Also, I hear a lot about RTAB limiters. Is that something I need or is it more for a non-street application?

---

it's fine for street use. i went with the powerflex poly RTABs and while they are better than worn OEM bushings, ultimately they're not the correct solution, as they do not allow full multi-axis articulation of the trailing arm (neither does rubber, but it allows more than poly does).

i've just recently picked up a set of bimmerworld sealed spherical RTABs that i personally think will be the best solution on the market for RTABs. they allow correct articulation of the arms, have a sealed OEM bearing (for longevity), and should be quiet with zero ride penalties. excited to install them.

peter