Suspension refresh

Hi all, I was curious to get any input on what all is required as im at 95k on my e90 m3. So far I have replaced the ZCP struts with EDC Bilsteins but I wanted to target all the control arms and rubber next.

I was thinking of doing both front lower arms with the sway bar link with inner and outer tie rods and it appears in the rear, there are 3 arms with bushings in them (each side), however it appears there maybe rubber in the wheel carrier and not sure what else to replace like subframe or diff bushings.

Thanks for any input.

This thread might be useful:

https://www.m3post.com/forums/showthread.php?t=1781245

Curious how was th improvement from the old zcp to the bilsteins? Did you go with b6 or 8? Thanks

osukf09 wrote

Curious how was th improvement from the old zcp to the bilsteins? Did you go with b6 or 8? Thanks

Good question. I've got 71k mi on my OE EDC shocks with Swift Sport lowering springs and thinking of replacing them with compatible b6. Also have a little bump steer so thrust arms look to be in my future.

At ~100k miles, if not before I intend on doing;

- Front control arms with spherical bushings
- Lower control arms
- Front swaybar bushings (OE)
- Rear subframe bushings (Solid)
- Rear differential bushings (OEM) + new hardware/bolts
- Rear swaybar bushings (OE)

Slight increase in NVH with the spherical front control arm bushings. No increase in NVM with the solid subframe bushings. Note: replacing rear swaybar bushings is best done when the subframe is dropped—so makes the most sense to do these when you're doing the subframe & diff bushings.

Anything further I would do on a case by case basis. See if there is any slack/cracking and replace as necessary.

Here's a great kit that covers pretty much everything on the front end apart from the swaybar bushings:

https://germanautosolutions.com/store/bmw-e82-e90-monoballs-and-control-arm-set-v2/

My top hats and bump stops were trash by 89k when I refreshed mine.

Upgraded to shaved top hats and E36 bump stops when I put Eibach springs.

I felt the difference in just this.

SilverSlug wrote

My top hats and bump stops were trash by 89k when I refreshed mine.

Upgraded to shaved top hats and E36 bump stops when I put Eibach springs.

I felt the difference in just this.

What were the symptoms of the bad top hats and how can you tell, mine looked fine? Also, how did you shave the top hats? I've got H&R Race springs on my stock EDC so would like to do that as well...although I think my shocks/struts are bad also. My bump stops were gone completely and put the E36 bump stops in thinking that was my problem but still feels like crap.

I got a pair of Dinan shaved top hats (OEM, but already shaved), so they were ready to go, but there is site online somewhere that I saw that also offers a service where they shave the top hats for you.

It will allow for more shock travel, even when you're lowered, so should feel a lot better, especially if you're slammed on H&R springs.

Also, are you sure you installed the bump stops correctly? You have to stuff them through that ring, which holds them in place when you pop them in (sorry I don't know the exact vocabulary for the parts).

sibhusky wrote

Hi all, I was curious to get any input on what all is required as im at 95k on my e90 m3. So far I have replaced the ZCP struts with EDC Bilsteins but I wanted to target all the control arms and rubber next.

I was thinking of doing both front lower arms with the sway bar link with inner and outer tie rods and it appears in the rear, there are 3 arms with bushings in them (each side), however it appears there maybe rubber in the wheel carrier and not sure what else to replace like subframe or diff bushings.

Thanks for any input.

I replaced All my components with FCP control arms on all 4 corners...so that way I have lifetime warranty coverage if needed to replace again down the road...paired with Bilstein "Bilstein gaurantees 1 million miles" lol - EDC compatible shocks and swift springs....also I upgraded to Purple stuff for my subframe and transmission bushing. Highly recommended....removes wheel hops when driving high speed. Lets just say it was a busy year for me when I hit 100k miles on my car. Goodluck

SilverSlug wrote

I got a pair of Dinan shaved top hats (OEM, but already shaved), so they were ready to go, but there is site online somewhere that I saw that also offers a service where they shave the top hats for you.

It will allow for more shock travel, even when you're lowered, so should feel a lot better, especially if you're slammed on H&R springs.

Also, are you sure you installed the bump stops correctly? You have to stuff them through that ring, which holds them in place when you pop them in (sorry I don't know the exact vocabulary for the parts).

Can you buy just the top hats or do you need the whole supplemental ride quality kit from Dinan?

I'm not certain I installed the bump stops correctly...now, depending on what you mean by "ring that holds them in place"

Sorry OP, didn't mean to thread jack. I also just got the GAS arms. I'm waiting for my Ohlins to come in but want to sort as much as I can now even with the stock EDC and springs my car came with.

These are the rings I'm talking about. 2nd photo shows how they pop in and sit in the boot gators. 3rd photo is how the bump stop goes inside the ring… so, when you pop the bump stop into the rubber gator boot, the ring will keep it in place.

And regarding top hats, I was about to have mine shaved down online, but was lucky enough to find a discounted Dinan kit for sale online.

Thanks I just ended up going with the FCP TRW front and rear control arm kits. I dont track my car so dont care too much for poly/monoball stuff and ill leave the subframe and diff alone for now. The lifetime warranty will allow me to just refresh these components after 40-50k if need be.

GotV8? wrote

I replaced All my components with FCP control arms on all 4 corners...so that way I have lifetime warranty coverage if needed to replace again down the road...paired with Bilstein "Bilstein gaurantees 1 million miles" lol - EDC compatible shocks and swift springs....also I upgraded to Purple stuff for my subframe and transmission bushing. Highly recommended....removes wheel hops when driving high speed. Lets just say it was a busy year for me when I hit 100k miles on my car. Goodluck

sibhusky wrote

Thanks I just ended up going with the FCP TRW front and rear control arm kits. I dont track my car so dont care too much for poly/monoball stuff and ill leave the subframe and diff alone for now. The lifetime warranty will allow me to just refresh these components after 40-50k if need be.

Which kits did you go with and how was the install? I’m over 156k miles on all original suspension parts. Looking at doing this in the fall, likely should replace struts too.