Dackel's replacement of rear suspension OE bushings with M3 ones…

[Dackelone]

Originally Posted by ubersteuer

...The rabbit hole is exactly why I'm afraid to do ANYTHING yet. ...

I really like the way my car drives/handles with the RSB and my Michelin PS3's. You can always wait until your suspension wears out - to make suspension upgrades. I keep telling myself I should really start replacing more things on my suspension. But so far I have not. Maybe this Spring I will get the urge to do it!


Dackel

[sjk9671]

So I just installed the Whitline sub-frame bushings. I have to say, getting the rear bolts back in was WAY harder than I remember when taking them out.

I even pulled them back out several times to make sure I wasn't stripping something. But they looked fine. I lined them up and then went in about 10 turns freely by hand but once they get about half way in I really encountered some serious resistance.

I pulled them back out and greased the threads and even so I had to use a piece of my jack handle for the last inch. They are all tight now.

Anyone else have this issue? I know 100% the bushings and sub-frame are lined up right. The front mounts bolts went in easy and I tightened them down to about the last 1/2 in before I put the rears in.

[Dackelone]

Originally Posted by sjk9671

So I just installed the Whitline sub-frame bushings. I have to say, getting the rear bolts back in was WAY harder than I remember when taking them out.

I even pulled them back out several times to make sure I wasn't stripping something. But they looked fine. I lined them up and then went in about 10 turns freely by hand but once they get about half way in I really encountered some serious resistance.

I pulled them back out and greased the threads and even so I had to use a piece of my jack handle for the last inch. They are all tight now.

Anyone else have this issue? I know 100% the bushings and sub-frame are lined up right. The front mounts bolts went in easy and I tightened them down to about the last 1/2 in before I put the rears in.

Did you mix up the bolts with the fronts ? I really can't say why you had a hard time with the bolts. Maybe order new bolts and swap them in on your next oil change.

I looked on RealOEM.com and the bolts don't seem to be of a one time use type. Maybe try using a magnet to see if those bolts are of a alloy/stretch type. ?

[sjk9671]

Originally Posted by Dackelone

Did you mix up the bolts with the fronts ? I really can't say why you had a hard time with the bolts. Maybe order new bolts and swap them in on your next oil change.

I looked on RealOEM.com and the bolts don't seem to be of a one time use type. Maybe try using a magnet to see if those bolts are of a alloy/stretch type. ?

I thought about that, but I believe they are the same front and back? The fronts went in no problem.....

Edit: according to realOEM, they are both #7. Part number: 33306793892
Torx screw with collar M12X110-10.9

http://www.realoem.com/bmw/enUS/show...07#33306793892

[BlackBMiLuc]

I can't wait to experience this difference!

[JWedd]

new to the 1er, and totally love this car. 2011 128i, M-Sport, 6MT, SULEV N51.

My ride also has Koni FSD shocks and struts, plus Eibach lowering springs and ZHP 18" wheels. It seems firmly planted to the road, taking foothill curves and wiggles in the pavement without a hint of wander.

I read this entire thread and did not see a mention--M-sports have some kind of M-type suspension components. But RealOEM does not list the M bushings numbers as factory in my car. I take it that means there is no hope that they are indeed already in place?

Thanks Dack for the good info and advice. I have spent many hours just reading on the forum and have gleaned a lot from you and many others.

John

[asbrr]

Originally Posted by JWedd

new to the 1er, and totally love this car. 2011 128i, M-Sport, 6MT, SULEV N51.

My ride also has Koni FSD shocks and struts, plus Eibach lowering springs and ZHP 18" wheels. It seems firmly planted to the road, taking foothill curves and wiggles in the pavement without a hint of wander.

I read this entire thread and did not see a mention--M-sports have some kind of M-type suspension components. But RealOEM does not list the M bushings numbers as factory in my car. I take it that means there is no hope that they are indeed already in place?

Thanks Dack for the good info and advice. I have spent many hours just reading on the forum and have gleaned a lot from you and many others.

John

John - the M-sport package does not change the subframe bushings. Unless the previous owner did them when he/she did the shocks/springs etc. Only way to know is to take a close look at the bushings, and even then may not be obvious if they are upgraded to M3 bushings without taking off one of the bolts and looking at the bushing itself.

More than likely they are stock....so upgrade!

[Dackelone]

JWedd

Originally Posted by asbrr

John - the M-sport package does not change the subframe bushings. Unless the previous owner did them when he/she did the shocks/springs etc. Only way to know is to take a close look at the bushings, and even then may not be obvious if they are upgraded to M3 bushings without taking off one of the bolts and looking at the bushing itself.

More than likely they are stock....so upgrade!

^^What he said! I think rear subframe bushings probably should be your next upgrade. Some people find the Koni FSD shocks to be too "soft" and end up going with Koni "yellows". I guess depending on your shock's condition would dictate what your next mod will be.

IF you do go with the M3/1M rear subframe bushings... I would also replace all six brake hoses with DOT approved stainless steel brake lines - bc you have to drop the rear axle to install the M3 bushings. .

Also for anyone with a e8x/e9x car... read this article in Bimmer Magazine...

The Ultimate Handling Machine
TC Kline’s suspension tuning transforms the entry-level 128i Coupe into a car that can rival the 1 Series M Coupe for pure driving fun.
http://www.bimmer-mag.com/issues/101...e#.WFLGFvkrLIU

[JWedd]

thanks gents...I'll have a bunch of time under the car in a few weeks with various fluid changes, brakes, water pump etc, so I'll do a close inspection of the bushings. It's possible they have the inserts also. With 60k miles, some bushing wear is to be expected.

John

[dojk]

Any idea the hardness of the M3 bushes?

Strongflex has them in PU now, was wondering if they would be a better option.

http://www.strongflexuk.co.uk/bmw/1-series/e81-e82-e87-e88-04-11/rear-subframe-rear-bush.html#.WGiImsvmjqA

[asbrr]

Originally Posted by dojk

Any idea the hardness of the M3 bushes?

Strongflex has them in PU now, was wondering if they would be a better option.

http://www.strongflexuk.co.uk/bmw/1-...l#.WGiImsvmjqA

The biggest difference is the M3 bushings are rubber with metal core. So it's hard to compare durometer ratings to the strongflex you listed. FWIW I have the Whiteline full bushings which are Poly, and although I had them installed at the same time as my B12 suspension, I can't say that I get terrible NVH from the rear of the car.

So if you're concerned about that, the poly bushings I don't think will add any significant harshness, at least not when we're talking about subframe bushings.

Other bushings (like the diff bushing etc) I can't comment on, as I've heard they can add harshness that is felt inside the car.

[dojk]

Considering the OE bushings are so soft with physical gaps inbetween, instead of getting them pressed out with gadgets and tools, won't it be easier to just cut them out?

Originally Posted by Dackelone

Ok, I finally went ahead and had my car’s rear bushings replaced with M3(nee… 1M) ones. The soft squishy rear suspension was really going on my nerves. The rear axle felt so over powered and twisted when ever I would go WOT upon exiting a corner. Or even just cruising down the road… the rear suspension would wiggle and wander on its own. I had basically gotten use to just going with the flow and riding out the wiggles and movement of the rear suspension. No more!

I had contacted my local BMW dealer about installing M3(nee… 1M) rear suspension bushing. My SA was curious because they had never done a repair like this before. But I was confident in them and know they could handle the job. The M3 rear suspension bushings have a list price over here of 39 euros each(156 euros in parts). You need four bushings total. Although the rear ones are different in design than the front sub frame bushings are.

When my SA looked up the TIS (BMW’s repair guide) they told me it would cost 170 AW’s in mechanic time units. My German dealer’s labor rate is 110 euros per hour. That equated to 294 euros in labor. That sounded like a really good deal to me. It was(more later…). Plus my SA always gives me 20% off parts and usually a pretty good break on labor too. So… I gave them the ok to go order the parts.

The first snag was that they needed to order a BMW special tool to install the bushings on the car. BMW’s TIS guide said that both bushings(front and rear) could be replaced while the axle was on the car. (…But that was not the case) SO… a few days later my guys received their special installing tool… and I booked a service date and loaner car(118d hatch). It was suppose to be a one day job. It ended up being a two day job!

The rear bushings were very easy to replace. But the front bushings of the rear sub frame required more work than previous thought. My guys tried to drop the axle as much as possible… but the problem was that while the rear bushings can be pressed out and back in while the axle is still bolted up to the car(only dropped six inches or so) the front ones can not. The rear bushings come out thru the bottom of the sub frame (axle) carrier. But the front bushings go in thru the TOP! So this requires you to drop the rear axle. That means the exhaust, brake lines, driveshaft, cross bar and a few other things have to be taken off the car. My poor car was a mess. But the guys at the dealership came thru for me. They were able to drop the rear axle and press in the forward M bushings. Then put everything back together and bleed the brakes. All in all it ran me an extra 200 euros than I had anticipated. I think they worked on my car for the better part of a day. So I think they cut me a break on the labor as best they could without bending me over. Still… it ended up costing me more than I thought it was going into this. But then again, I knew 440 euros for this job complete sounded too good to be true. In the end it came to 600 euros with all my discounts. I know that’s a lot but it was worth it!


I took some pictures of the old OE axle bushings. What struck me right away was how soft they are when you hold them. Also how little they weigh. Also take note of the huge gaps in rubber inside the bushings. They are by no means solid. The M bushings on the other hand must weight at least twice or three times as much. And have a more solid feel to them. The M bushings are made from hard rubber and have no give to them at all. At least not in your hand.




So… how does the car ride now with the M rear axle bushings? FANTASTIC!!! Before (//M bushing install) what bothered me the most are these three things:

1). When traveling at low speeds (25 mph or so) on a flat road… when you encounter bumps or go over recessed man hole covers, the rear end of the car would wiggle or step out somewhat. It was really going on my nerves.

2). When giving accelerating out of corner… the rear end would windup and the rear end would go and do what it wanted. The rear axle felt very rubber-y like. It was hard to predict what the rear end would do when giving the car some power out of the turns. Enter some bumps on the exit and it only made things more dramatic.

3). When pitching the car hard into a turn… the rear end would not take on a “set”. The rear end felt as though it was being help in place via rubber bands. It made it hard to feel what the rear end would do “thru” any hard corning turn. What I realized (after the M bushings were installed) was that I was more riding things out thru the turns, rather than “driving” car thru the turns.



Now this is what I noticed most after the M bushing install:

Gone is ALL the wiggle (& movement) from the rear end!!! When going over (ever so slightly)bumpy roads or manhole covers – there is no wiggle from the rear end. The car just feels so much more solid. As one would expect of any sporting BMW. While there is no wiggle, the impacts of said bumps are not over harsh in the least. I would say that the ride or impacts that the rear end absorbs is no more than 10% firmer than the OE bushings. But gone is all movement of the rear axle.

Gone too is that “rubber band” feeling you get when trying to launch the car out of the turns. The rear end just plain STICKS and hunkers down. Gone is all that slack and movement. The rear end just feel “planted” and more solid.

Now when you through the car into a turn or even just take it easy… when the rear end loads up with corning forces… it just feels (much more)secure and reassuring. It is not going to twist or catch you off guard like the OE bushings. No wobble or axle hop, skip, jumping over bumps on the exit. The rear end just stays planted. It is truly amazing how these bushings have transformed the way the car drives.


One thing I really did not expect is how much better the car feels at high speeds (120 mph and above). The car just handles so much better now. I always thought the movement from the rear suspension was due to the progressive rear springs(since my car is a 2010). I thought perhaps the 2011’s and later cars had a better handling rear end due to the linear springs. But all that wiggle and movement is due to the soft weak OE axle bushings.

Another thing that surprised me is how the front of the car’s suspension seems to be working better now. Maybe this is all in my head, but I feel like the “whole car” feels like it is way more solid now than before.

Really the only negative thing I can say about these bushings is on all cobble stone roads the ride is noticeably more rough. I’d say 20% rougher. But on normal roads or even badly paved roads… the ride is almost the same. I’d say at most 10% stiffer. Even when you hit a pot hole dead on… there is no crash and boom – like one would think. The car just absorbs the impact and moves on.


SO… I would say to anyone considering this mod DO IT! You won’t be sorry. I am not.

I can say that I now know this will push me to get the rest of the M bits on my car ASAP. Like the front control arms and tensile rods, ect. I think proper shocks and springs will be in my future as well.


Btw… I did not have the chance to take any pics during the install. I only took some pictures of my old OE bushings. I did find some pictures on the web that I thought would be useful. I have included some links bellow to some relevant threads.


Dackel




M3(1M) rear axle bushings...

M3 bushing on LEFT is the front bushing. Bushing on right is the rear axle bushing.
Attachment 633636

M3 bushing LEFT, OE soft bushing RIGHT.
Attachment 633637

Attachment 633638

OE 135i soft rubber axle bushings...
Attachment 633639

Attachment 633640

Attachment 633641

Note: the gaps of rubber - that give the bushings too much movement or squish/rubbery feel!
Attachment 633642

Attachment 633643












Rear of car "rubbery" under hard acceleration?
http://www.1addicts.com/forums/showthread.php?t=631854

Alpina B3 Lux great suspension writeup...

M3 suspension components + Quaife Limited Slip Differential
http://www.e90post.com/forums/showthread.php?t=379775

BMWFanatics Forum
http://www.bmwfanatics.co.za/archive...ead-23348.html


You can use M3 or 1M bushings. They are one in the SAME part(s). You need two for the front part of the rear axle carrier and two for the rear part of the axle carrier.

(2) bmw #33312283382
(2) bmw #33312283383

I paid 40 euros for each rear bushing or 160 euros for all four. Thats without 19% German sales tax. I think the price has gone up slightly since then.


Also... for anyone thinking about also replacing their trans rear saddle mounts... read these two great posts by 1addict member: Wolfe

Some great reading on the trans M3 mounts for our e82's...

Anyone fitted e46 M3 transmission mounts?
http://www.1addicts.com/forums/showt...ghlight=e46+M3

DIY: Upgrading/replacing transmission mounts
http://www.1addicts.com/forums/showt...ghlight=e46+M3



and...

My new Michelin PS3’s 225’s & 255’s…
http://www.1addicts.com/forums/showthread.php?t=510873

[Luftmeister]

Question on the measurable improvement... Does the car just feel better or has anyone definitively seen so with improved laptimes or the like?

-Cheers

[Dackelone]

Originally Posted by Luftmeister

Question on the measurable improvement... Does the car just feel better or has anyone definitively seen so with improved laptimes or the like?

-Cheers

I have not seen anyone post before and after lap times. But I am sure the car would be faster(lap times) than stock. The M3 rsb get rid of the "rubber band" feeling from the rear suspension. You notice this more when your tuned and you start to apply power mid corner/apex... the rear axle doesn't go every which way when you get on the power with the M3 rsb. Its so much more controlled and planted back there.

Dack

[3k1n]

Which Rear subframe bushings should I get? My head is spinning.
-M3
-Whiteline
-Powerflex,
-Agk

I plan on renting the bushing removal tool and the car will just be doing spirited driving. I dont mind NVH increases. Please help me decide

[Dackelone]

Originally Posted by 3k1n

Which Rear subframe bushings should I get? My head is spinning.
-M3
-Whiteline
-Powerflex,
-Agk

I plan on renting the bushing removal tool and the car will just be doing spirited driving. I dont mind NVH increases. Please help me decide

I would get the M3/1M bushings. Very little increase in NVH but very much improved control under performance type driving. One of the best mods I've done to my 135i.

[dojk]

Hi,

Any recommendations what the torque numbers are for putting the car back together?
I have my Strong flex RSB ready to go in.

Thanks.

[BoLLo_]

I'm also keen on the forum's consensus regarding torque values.

Does anyone have a recomendation for the ideal IDs for pipe for a DIY tool? I'm guessing something just above 75mm and 80mm.

[Dackelone]

dojk
BoLLo_

The bolts that secure the rear subframe to the chassis are a one time use(stretch bolts). So when you order new bolts at a BMW dealer, have them look up the torque values. Any dealer should be able to tell you the torque value.

[dojk]

Thanks.
My workshop is fitting the RSBs now, but they are asking which was is 'UP' for them.

I need an answer for them. Any ideas guys?

[BoLLo_]

Originally Posted by Dackelone

dojk
BoLLo_

The bolts that secure the rear subframe to the chassis are a one time use(stretch bolts). So when you order new bolts at a BMW dealer, have them look up the torque values. Any dealer should be able to tell you the torque value.

Thanks for pointing that out, Dackelone.

My local dealer doesn't have any in stock. I doubt they replace them if they don't have any in stock but that is beside the point.

I see in the Bentley manual the tightening torque is 100NM (73.7 ft.lb)

dojk
I don't have time to read the whole thread now but I seem to remember some clue regarding the correct orrientation in this thread: http://www.1addicts.com/forums/showt...frame+bush+diy

[Dackelone]

Originally Posted by BoLLo_

I don't have time to read the whole thread now but I seem to remember some clue regarding the correct orrientation in this thread: http://www.1addicts.com/forums/showt...frame+bush+diy

Yep, the forward RSB mounts can press out/in from bellow the subframe. The real PITA are the rear ones, which you need to drop the rear axle/subframe to get enough room for the press/tool to get up in there and work!

My dealer had to break open the rear brake lines and lower the axle onto a cart positioned under the car to work on those two rear subframe bushings. Them they had enough room to use that on the car press tool. Then they bled the ABS block and brakes with the BMW ISTA tool. Looking back, I think I should have also replaced my brake lines at that time. Ohh well. Hind sight is 20/20.

Dackel