Bushing choices

[Lucien316]

I’m thinking of running new diff bushings, subframe, and engine mounts for my 1M. For tranny mount getting rogue. Someone recommended OEM 1M bushings but interested in aftermarket. Thoughts? Don’t want excessive nvh but better if there’s such thing in this department. Going to be pushing pretty big Hp. Thanks

 

[doublespaces]

I'm going to go out on a limb and say your options are shared with the 135i? @martymil may have some advice.

 

[Lucien316]

I have spoken to him. He recommended oem. AKG said if I go poly, to do the same uniform with mount and trans as one unit and same dif and subframe as a unit. That they work in unison and should be same stiffness. The only option they suggested otherwise was like a rogue trans bushing and oem elsewhere. They’re sold out of their poly front set up for months and ecs carries them(street/race) version for dif and subframe, but I don’t think they have trans and engine mount bc lacking engine mount. Getting a revtech motor mount was discouraged by AKG and rogue. So maybe just oem all around except rogue trans. I don’t know.

 

[N54gasm]

I am a big poly fan for bushings. I have some AKG motormounts/trans mounts about to go in, but the complete rear end was swapped to polyurethane and is a huge improvement. Just not a smooth drive like oem.

 

[ShocknAwe]

Here's what I suggest, and having tried almost every option I'd never deviate from this but it's your car! Have fun exploring options too I enjoyed the journey. There is minimal NVH increase with this and is perfect for a street/weekend track car.

Engine: Genuine 335is "IS" engine mounts. This is a stock mount on driver and harder mount on passenger. If you go too stiff here it increases NVH severely. I like the VTT reinforcement plates but they raised the engine and the COG which I found undesirable and removed them.

Trans: RE mounts. These are solid and stiff but alow for some movement which is desireable.

RSFB: SOLID ALUMINUM. I recommend Bimmerworld for this but turner sells a set too.

Differential: stock. This is where your NVH comes from in the rear

 

[Torgus]

Differential: stock. This is where your NVH comes from in the rear

Not even a lock down kit to help with wheel hop?

My solid diff mounts added diff whine which you hear above 45 mph but that is it. No VH, just N.

 

[houtan]

I did the condor speed shop Delrin diff bushings. I didn’t notice any nvh tbh. My diff is an m factory helical.

I also have the revshift motor and trans mounts and I love them. My idle is slightly raised to 750 but for me the benefits outweigh any nvh at idle. Everything feels more direct.

 

[ShocknAwe]

Not even a lock down kit to help with wheel hop?

My solid diff mounts added diff whine which you hear above 45 mph but that is it. No VH, just N.

I think diff lockdowns are great. In defense the OP did specify bushings.

 

[SLOWESTN54]

A little of topic but what's the best way to install solid subframe bushings?

 

[Torgus]

A little of topic but what's the best way to install solid subframe bushings?

At a shop

I would drop the subframe, do the diff and subframe bushings, upgrade the annoying 'middle' brake lines to SS. If you have a stock diff upgrade that at the same time. Add a diff lockdown kit, change arms, other suspension bushings etc. etc. Do it all at once while you are back there messing around is my vote.

 

[houtan]

Is the lockdown needed if the bushings are upgraded?

 

[Torgus]

Is the lockdown needed if the bushings are upgraded?

I don't see how it could do much of anything with the diff held in place solidly by 3 now 100% solid mounting points. I guess on a very hard launch it could act like giving it a 4th mounting location? There was a diff lockdown kit that vwvetish or someone like that used to sell which made a 4th 'real' mounting point.

I had my diff lockdown plate lying around and had it installed it at the same time as the solid diff and subframe bushings. It can't hurt and it relatively small money. I also never wanted to have wheel hop at the track because of those rear soft bushings BMW put on e90s. Once you blow an axle it gets old real quick.

edit:
here is the model which gives you the 'real' 4th mounting point: https://www.spoolstreet.com/threads/whats-everyones-take-on-this-lockdown-brace.3322/ & https://www.n54tech.com/forums/showthread.php?t=38313 & https://www.e90post.com/forums/showthread.php?t=799038

 

[N54gasm]

I did my subframe bushings in the car and was quite easy. Using the tool (https://www.ebay.com/itm/333158778716)/ Also using the trailing arm bushing tool from ecs (https://www.ecstuning.com/b-bav-auto-tools-parts/trailing-arm-bushing-tool-set/b8800101~bat/)

The diff lock down by all means helps alot. I had massive traction issues until I redid the rear end suspension/bushings and solved 90% of my spinning aint winning issue lol.

 

[houtan]

Thanks. Yeah the reason why I asked is with the Delrin diff bushings my diff is rock solid so for me it sounds like it’s not needed. Just wanted to make sure I wasn’t missing something.

 

[Jeffman]

At a shop

I would drop the subframe, do the diff and subframe bushings, upgrade the annoying 'middle' brake lines to SS. If you have a stock diff upgrade that at the same time. Add a diff lockdown kit, change arms, other suspension bushings etc. etc. Do it all at once while you are back there messing around is my vote.

I had purchased all of the bushings, arms, lock down kit, etc for the rear end of my ‘08 335xi last year. Finally getting a Quickjack to help me raise the car to hopefully get to that work this year. Haha

 

[Jeffman]

I had purchased all of the bushings, arms, lock down kit, etc for the rear end of my ‘08 335xi last year. Finally getting a Quickjack to help me raise the car to hopefully get to that work this year. Haha

And here I am six months later…I got the QuickJack and planning to drop the subframe this Spring. Started to watch YouTube videos on dropping the subframe. The Bimmerbarn one seems very good but he described a rather involved process to disconnect the parking brake cables that requires disassembling the center console which looked like a major PITA. Is it really necessary to take apart the center console to drop the subframe?

 

[jzx_andy]

And here I am six months later…I got the QuickJack and planning to drop the subframe this Spring. Started to watch YouTube videos on dropping the subframe. The Bimmerbarn one seems very good but he described a rather involved process to disconnect the parking brake cables that requires disassembling the center console which looked like a major PITA. Is it really necessary to take apart the center console to drop the subframe?

I don't think its necessary.

Take off the handbrake boot, lower the handbrake fully, and use a pry bar or screwdriver to lock the spring mechanism into the service position.

Then remove calipers/rotors/parking brake shoes/parking brake shoe expanders, and you can get the cables out from the inside of the knuckles very easily. It's a bit of work, but way less tedious than removing the centre consoles and working inside the car. Jake Spence has a video on his channel of a rear subframe removal/teardown which outlines an "easy" process in very high level terms. It'd be a couple of years old at this point.

 

[Jeffman]

I don't think its necessary.

Take off the handbrake boot, lower the handbrake fully, and use a pry bar or screwdriver to lock the spring mechanism into the service position.

Then remove calipers/rotors/parking brake shoes/parking brake shoe expanders, and you can get the cables out from the inside of the knuckles very easily. It's a bit of work, but way less tedious than removing the centre consoles and working inside the car. Jake Spence has a video on his channel of a rear subframe removal/teardown which outlines an "easy" process in very high level terms. It'd be a couple of years old at this point.

Thanksamiilion!