Differential Bushings - What are you running?

[LukesM]

I need to swap out the diff bushings and wish there were some stock like bushings that could be pressed in vs replacing the whole cover.

This is for a street car and I don’t want to run solid but would consider some poly bushings if they didn’t significantly increase NVH.

All I’ve seen for poly are the ECS and Powerflex black bushings.

What are you guys running?

[Tbonem3]

AKG black poly, it's like 90 or 95a hardness, so very firm, but not like delrin or nylon. There's some whine, but it's kinda cool. Best part is the power transfer, it's very violent compared to stock (though stock was worn out) .

[Robert's_BMW]

I need to swap out the diff bushings and wish there were some stock like bushings that could be pressed in vs replacing the whole cover.

This is for a street car and I don’t want to run solid but would consider some poly bushings if they didn’t significantly increase NVH.

All I’ve seen for poly are the ECS and Powerflex black bushings.

What are you guys running?

I have AKG Poly 75D subframe bushings since they don't add any NVH. Every other bushing is OE since they work great and add no NVH. Only other bushings I would consider are monoball for the FCAB/RTAB.

[heinzboehmer]

I've also got the 95A AKG poly bushings. They do add a significant whine, which is most pronounced around 80mph or so. In the near future, I want to replace all diff bushings with OEM and my poly subframe bushings with CMP solid bushings.

[oceansize]

As of just a couple hundred miles ago I'm CMP subframe, CMP RTAB, and OE Diff (I bought a new OE diff cover). Good combo. I came from powerflex poly yellow subframe, oe rtabs, and oe diff (shot). Response is excellent and no whine (that I can hear).

[BMWahba]

I’m going to run OE diff, fall line rtab, and solid aluminum subframe.

[COVID-19]

Running AKG’s 95A (powerflex sucks). I believe a few members have done the rears with AKG and the front bushing oem and there’s no whine.

[Tbonem3]

Running AKG’s 95A (powerflex sucks). I believe a few members have done the rears with AKG and the front bushing oem and there’s no whine.

I though it was the other way 'round.

[COVID-19]

I though it was the other way 'round.

Something like that lol I can’t remember

[jayjpl]

Currently running Condor's Poly bushings for subframe and differential, stock was worn so replaced with poly, i like them

[Ruley]

I had the ecs poly front with a new diff cover +aluminum subframe bushings when I put my rear reinforcements in (reddish plates and vincebar+front cups)and wasn’t a fan. Diff whine was very noticeable up around 75mph and beyond. Some might tolerate it but I replaced the front poly diff bushing with a new bmw one and it was just like stock again. It wasn’t like a dog box/sequential transmission but enough for me to swap it.

[AussieE46M3]

As others have said, I also use to have the full powerflex setup (subframe yello, diff and RTAB black) and ended up binning the lot for solid aluminium subframe, stock diff & Monoball RTAB.

This setup is OE quiet unlike poly and handles infinitely better.

If you're looking for a cheaper alternative to replacing the diff cover, it has been suggested that E36 rear diff bushes fit into the E46 M3 cover however, I have not confirmed that for myself.

[Dash1]

As others have said, I also use to have the full powerflex setup (subframe yello, diff and RTAB black) and ended up binning the lot for solid aluminium subframe, stock diff & Monoball RTAB.

This setup is OE quiet unlike poly and handles infinitely better.

If you're looking for a cheaper alternative to replacing the diff cover, it has been suggested that E36 rear diff bushes fit into the E46 M3 cover however, I have not confirmed that for myself.

Yes but the e36 rubber is softer

[Dash1]

I have Powerflex rtabs and diff bushings (95A) with turner aluminium/delrin subframe bushings.

[LukesM]

Lots of good feedback here. Thanks for that. Sounds like oem front diff and 95A AKG rear diff would potentially work and not be too noisy.

I already bought stock RTABs with limiters that I need to install. Trying to decide on Subframe bushings as well.