M3 Rear Subframe Bushings Rubber vs. Aluminum

[chichicastenango]

Hello. I was looking at these two sets of rear subframe bushings and was just wondering what the difference would be? I noticed one is aluminum and the other is rubber. Is there a better option between the two?

https://www.turnermotorsport.com/p-1...ubber-e82-e9x/

https://www.turnermotorsport.com/p-1...minum-e82-e9x/

[dtla1]

Sorta related, but someone is selling a set of Turner Aluminim ones right now if you decide to go that route.

https://www.1addicts.com/forums/show....php?t=1639773

[chichicastenango]

Originally Posted by dtla1

Sorta related, but someone is selling a set of Turner Aluminim ones right now if you decide to go that route.

https://www.1addicts.com/forums/show....php?t=1639773

Thanks, I'll look into it.

[zx10guy]

Unless you have smooth as glass roads or this is a track only car, I cringe at how harsh the ride would be with solid bushings.

[chichicastenango]

Originally Posted by zx10guy

Unless you have smooth as glass roads or this is a track only car, I cringe at how harsh the ride would be with solid bushings.

I live in Canada where the winters destroy our roads with potholes in the summer.

[zx10guy]

Originally Posted by chichicastenango

I live in Canada where the winters destroy our roads with potholes in the summer.

Then why are you considering solid bushings?

[chichicastenango]

Originally Posted by zx10guy

Then why are you considering solid bushings?

Only one's I can seem to find. Even when I asked about the difference from turner they told me that it's the same part. Do you know where I can find the poly version?

[fast1eddy]

Search for Whiteline bushings I bought mine from Amazon. Had to wait for them but the best price I could find. I think I found them under E90 chassis designation. Exact same part Whiteline KDT917

[MightyMouseTech]

Originally Posted by zx10guy

Unless you have smooth as glass roads or this is a track only car, I cringe at how harsh the ride would be with solid bushings.

The F30 cars and newer don't even use bushings anymore. Subframe directly bolted to pins in the chassis. Not sure it would be that bad.

[zx10guy]

Originally Posted by MightyMouseTech

The F30 cars and newer don't even use bushings anymore. Subframe directly bolted to pins in the chassis. Not sure it would be that bad.

I think if the chassis was designed with that in mind from the beginning then maybe. But our cars were not.

I remember life with an old project car I had. Had urethane bushings, Bilstein struts, Eibach springs, bigger rear sway bar, Koni yellow shocks, and caster plates. The thing rode hard. In the beginning it was novel. It got old quick driving through the messed up roads in DC. Eventually, that harshness translated into broken suspension pieces. Won't do that again.

[zx10guy]

Originally Posted by chichicastenango

Only one's I can seem to find. Even when I asked about the difference from turner they told me that it's the same part. Do you know where I can find the poly version?

I'd go with the first option in your post which are the stock M3 rubber bushings and call it a day.

[dtla1]

https://www.suspension.com/kdt917

[kaputt]

I have the M3 bushings installed and it really transformed the car without being too punishing. If you could only ever do one mod to this car, that would be one I would recommend.

[tracer bullet]

Originally Posted by kaputt

I have the M3 bushings installed and it really transformed the car without being too punishing. If you could only ever do one mod to this car, that would be one I would recommend.

I did the same and feel the same as well. The M3 bushings eliminated the rubber band rear end snap and though the ride got firmer it isn't bad even in MN. I think the solid bushings probably actually wouldn't be a terrible ride either, and would be livable, but since the M3's totally did the job I guess I don't see the need to go a step further. To each their own of course, typically my mentality is to go that step further.

[Rmtt]

Check with chris_flies .

He went with one brand (I can't remember)....but it was a good price and he said he really liked them.

[chichicastenango]

Originally Posted by dtla1

https://www.suspension.com/kdt917

I've seen them mentioned. How do they compare to the M3 bushings?

[ShocknAwe]

I noticed no difference in NVH or ride quality between stock rubber with poly inserts, and solid aluminum from bimmerworld.

There was a huge difference in suspension response and rear end stability though.

[dtla1]

Originally Posted by chichicastenango

I've seen them mentioned. How do they compare to the M3 bushings?

Easier to install, cheaper. I haven't driven a car with the M3 bushings but based on other people's feedback, I would say the white line are on par if not a touch better than the M3 ones, but again, cheaper and much easier to install.

[duder13]

Originally Posted by dtla1

Easier to install, cheaper. I haven't driven a car with the M3 bushings but based on other people's feedback, I would say the white line are on par if not a touch better than the M3 ones, but again, cheaper and much easier to install.

Yeah, AFAIK, in terms of stiffness: OEM < poly inserts < M3 (albeit a big jump) < poly < aluminum

I got poly, and, while they’re easier to install at home, my shop didn’t really charge me much less to install the 2-piece, so I probably would go all the way to aluminum if I had a do-over.

[ShocknAwe]

Originally Posted by duder13

Yeah, AFAIK, in terms of stiffness: OEM < poly inserts < M3 (albeit a big jump) < poly < aluminum

I got poly, and, while they’re easier to install at home, my shop didn’t really charge me much less to install the 2-piece, so I probably would go all the way to aluminum if I had a do-over.

Seriously, go aluminum or just do inserts.

Key thing in all this though is to keep the diff mounts STOCK.

[Suprgnat]

Originally Posted by ShocknAwe

Seriously, go aluminum o̶r̶ ̶j̶u̶s̶t̶ ̶d̶o̶ ̶i̶n̶s̶e̶r̶t̶s̶.

FTFY

[duder13]

Originally Posted by ShocknAwe

Seriously, go aluminum or just do inserts.

Key thing in all this though is to keep the diff mounts STOCK.

Unless you're doing the job yourself, because the 2-piece poly install is easier.