[Chris@codemybimmer]

My phone ran out of batteries during the install so I didnt get much real world pictures. But i pulled some diagrams which is just as good.

Difficulty rating:
6/10
Amount of time taken:
2 hours

BMW ISTA's steps


Tools Required:
1 - Jack
2 - Jacking Pads
2 - Jack Stands
E-torx socket set - in the range of 20-14 (I dont remember exactly which ones, i just tried until i got ones that work)
1 - 16mm socket
1 - 8mm socket
1- Vice Grip

Brief descirption of what needs to be done:
ISTA's steps do work if you are replacing your sway bar with a stock one then you'll be fine. If replacing with an aftermarket, there will be more work.
You will need to lower the rear sub frame of your car in order to install your new sway bar. It will make your life a lot easier to do this first before unbolting the bushings.

Instructions:
Step 1:
Jack your car up from the rear central jacking point (on the diff).
Beware: do not jack your car from the rear diff cover or you will break it.

Step 2:
Using jack stands and jacking pads rest lower your car onto the rear 2 side jacking points.

Step 3:
Remove rear wheels

Step 4:
Unbolt Sway link from sway bar (both sides)
I have highlighted the sway link here stolen from Yuqi's thread:

This bolt is free spinning so it is tricky if it is your first time doing this
To do this you use a vice grip, clamp it down on the opposite side of the bolt to stop it from spinning.
Unbolt the 16mm bolt.

Step 5:
unbolt the front half of the fender liner with 8mm socked. Your goal is to gain access to the sub frame mounts which is behind the fender liner by the rocker panel.

For the remaining steps we can refer to this diagram:


Step 6:
Refer to point 1
This is the part you need access to behind the fender liner
there are two e-trox bolts here. unbolt them with the 16 e-torx socket (both sides)

Step 7:
Refer to point 2
These bolts holds the front half of the sub frame to your car. They are also extremely long. unbolt with 18 e-torx socket (both sides)

Step 8:
Be extremely cautious with this step
Slowly lower your jack and the front of of the sub frame will begin to lower.
WATCH YOUR BRAKE LINES AND LOWER FIREWALL.
I lowered it to a point where it just barely touched the lower firewall and the brake lines were extended but not to full length.

Step 9:
Refer to point 3
unbolt 2 e-etorx 16 bolts holding the sway bar bushings in place. (both sides)
looks like this:


Step 10:
Take the OEM sway bar out. I have no good description of how to do this... just wiggle and pull the bar out towards the driver side.

Step 11:
Feed new one back in bolt bushings back in.
Jack up the rear diff, bolt the rear subframe back on (all subfgrame bolts are 65 ft-lbs torque.


Step 12:
Sit back, relax and have a drink with mr. walker

[Smee]

tagged

[M47]

^ Are you planning to get sway bars?

[Smee]

I am planning on the rear one yes

[Thisisdudewhoru]

Which rear did you get? What car model do you have?

[Smee]

I have a 435d xdrive. This has a 12mm rear arb. I am fitting a 15mm rear arb from the m135i.

[Polo08816]

Originally Posted by 1lyfe

My phone ran out of batteries during the install so I didnt get much real world pictures. But i pulled some diagrams which is just as good.

Difficulty rating:
6/10
Amount of time taken:
2 hours

BMW ISTA's steps


Tools Required:
1 - Jack
2 - Jacking Pads
2 - Jack Stands
E-torx socket set - in the range of 20-14 (I dont remember exactly which ones, i just tried until i got ones that work)
1 - 16mm socket
1 - 8mm socket
1- Vice Grip

Brief descirption of what needs to be done:
ISTA's steps do work if you are replacing your sway bar with a stock one then you'll be fine. If replacing with an aftermarket, there will be more work.
You will need to lower the rear sub frame of your car in order to install your new sway bar. It will make your life a lot easier to do this first before unbolting the bushings.

Instructions:
Step 1:
Jack your car up from the rear central jacking point (on the diff).
Beware: do not jack your car from the rear diff cover or you will break it.

Step 2:
Using jack stands and jacking pads rest lower your car onto the rear 2 side jacking points.

Step 3:
Remove rear wheels

Step 4:
Unbolt Sway link from sway bar (both sides)
I have highlighted the sway link here stolen from Yuqi's thread:

This bolt is free spinning so it is tricky if it is your first time doing this
To do this you use a vice grip, clamp it down on the opposite side of the bolt to stop it from spinning.
Unbolt the 16mm bolt.

Step 5:
unbolt the front half of the fender liner with 8mm socked. Your goal is to gain access to the sub frame mounts which is behind the fender liner by the rocker panel.

For the remaining steps we can refer to this diagram:


Step 6:
Refer to point 1
This is the part you need access to behind the fender liner
there are two e-trox bolts here. unbolt them with the 16 e-torx socket (both sides)

Step 7:
Refer to point 2
These bolts holds the front half of the sub frame to your car. They are also extremely long. unbolt with 18 e-torx socket (both sides)

Step 8:
Be extremely cautious with this step
Slowly lower your jack and the front of of the sub frame will begin to lower.
WATCH YOUR BRAKE LINES AND LOWER FIREWALL.
I lowered it to a point where it just barely touched the lower firewall and the brake lines were extended but not to full length.

Step 9:
Refer to point 3
unbolt 2 e-etorx 16 bolts holding the sway bar bushings in place. (both sides)
looks like this:


Step 10:
Take the OEM sway bar out. I have no good description of how to do this... just wiggle and pull the bar out towards the driver side.

Step 11:
Feed new one back in bolt bushings back in.
Jack up the rear diff, bolt the rear subframe back on (all subfgrame bolts are 65 ft-lbs torque.


Step 12:
Sit back, relax and have a drink with mr. walker

I've attached a set of ISTAD Rheingold documents for front and rear suspension work (to include sway bar removal and installation).

[Sweeney921]

Few questions for OP, I'm glad that you made this thread!

- can the subframe mounting bolts be re-used?
- can the sway bar end links be re-used?
- did the exhaust get in the way?
- is an alignment required afterwards?

Some of the answers are pretty obvious, but this is the first mod that I've done on this car so I'm being overly cautious. Thanks for the help!

[Triharderken]

To be clear, there is no need to lower the rear subframe if you’re installing the M135i bar?

[Anthony1s]

Hi,

Does "replace bolts" mean they are torque to yield bolts? My mechanic is telling me they are tty bolts and BMW is telling him they are over $1000 to replace.

[Spielzeugauto]

Just finished this install last night. What a PITA! Having the bar sandwiched in the subframe like that is stupid, but I got it.

Few tips: a 10mm 16 point wench works well on the E12 (E14?) bolts holding the sway bar brackets on. There is not much room for a socket.

Also no need for a vise grip on the end links, they have a T25 (I think, maybe T20) to keep it from spinning while you get the nut with a 16mm wrench.

[sspade]

Originally Posted by Spielzeugauto

Just finished this install last night. What a PITA! Having the bar sandwiched in the subframe like that is stupid, but I got it.

Few tips: a 10mm 16 point wench works well on the E12 (E14?) bolts holding the sway bar brackets on. There is not much room for a socket.

Also no need for a vise grip on the end links, they have a T25 (I think, maybe T20) to keep it from spinning while you get the nut with a 16mm wrench.

Which rear bar did you upgrade to?

I have the BMW 15mm solid bar sitting in my garage. I want it on bad but dealer has quoted just over a grand to install...

[Spielzeugauto]

Originally Posted by sspade

Which rear bar did you upgrade to?

I have the BMW 15mm solid bar sitting in my garage. I want it on bad but dealer has quoted just over a grand to install...

Haha no it's definitely not a grand of work. A few hours of swearing at the German engineers, but that's it.

I did the H&R 20mm. Makes a nice difference but haven't had a chance to push the car hard yet

[sspade]

Originally Posted by Spielzeugauto

Haha no it's definitely not a grand of work. A few hours of swearing at the German engineers, but that's it.

I did the H&R 20mm. Makes a nice difference but haven't had a chance to push the car hard yet

HA HA - yeah I know.

Thats what BMW quoted me.

How far did you have to lower the rear subframe to swap bars?

Can you give a rough estimate in inches?

Mind sharing what tool/jack you used to support subframe when lowering?

[Spielzeugauto]

Something was kinda funky with mine, because even with all the described bolts out I could only get the subframe to drop about 2-3 inches. I had a regular aluminum racing jack under the differential but it wasn't necessary as something else was holding it from dropping.
It was enough space, but it was not a generous amount.

[sspade]

Originally Posted by Spielzeugauto

Something was kinda funky with mine, because even with all the described bolts out I could only get the subframe to drop about 2-3 inches. I had a regular aluminum racing jack under the differential but it wasn't necessary as something else was holding it from dropping.
It was enough space, but it was not a generous amount.

Interesting... appreciate that tid-bit. How did you get the subframe back up into place before tightening bolts? Im assuming its heavy as f'k which is why Im so hesitant to do this without a proper subframe jack...

Or were you on a lift, therefore allowing you to use a stationary jack while moving lift up and down slightly to raise and lower subframe (onto fixed jack).

[Spielzeugauto]

The car was high up on jack stands, with the racing jack under the differential just in case. So when I was done I just jacked the diff/subframe back up into place and bolted it up.

[sspade]

Originally Posted by Triharderken

To be clear, there is no need to lower the rear subframe if you’re installing the M135i bar?

Is there anyone out there that can answer this question, definitively?

I have the same OEM 15mm bar that Im dying to get installed. OP says if you are replacing with stock parts then you should not need to drop sub frame... can anyone confirm?

[NISFAN]

Originally Posted by sspade

Is there anyone out there that can answer this question, definitively?

I have the same OEM 15mm bar that Im dying to get installed. OP says if you are replacing with stock parts then you should not need to drop sub frame... can anyone confirm?

That is unhelpful misinformation, you definitely do need to lower the subframe, regardless of OEM bar or not.

Another tip to add to this great DIY....for a little bit more room, I loosened the rear subframe bolts too. As mentioned, they are long, so you can wind them out an inch. They still hold the subframe, but this allows it to tilt down at the front a little more. The fuel filler pipe restricts access on the right side of the car, so this last step makes it easier.

[sspade]

Originally Posted by NISFAN

That is unhelpful misinformation, you definitely do need to lower the subframe, regardless of OEM bar or not.

Another tip to add to this great DIY....for a little bit more room, I loosened the rear subframe bolts too. As mentioned, they are long, so you can wind them out an inch. They still hold the subframe, but this allows it to tilt down at the front a little more. The fuel filler pipe restricts access on the right side of the car, so this last step makes it easier.

Thank for you for confirming!

[Triharderken]

Originally Posted by NISFAN

That is unhelpful misinformation, you definitely do need to lower the subframe, regardless of OEM bar or not.

Another tip to add to this great DIY....for a little bit more room, I loosened the rear subframe bolts too. As mentioned, they are long, so you can wind them out an inch. They still hold the subframe, but this allows it to tilt down at the front a little more. The fuel filler pipe restricts access on the right side of the car, so this last step makes it easier.

[QUOTE=NISFAN;24674869]

Originally Posted by sspade

Is there anyone out there that can answer this question, definitively?

I have the same OEM 15mm bar that Im dying to get installed. OP says if you are replacing with stock parts then you should not need to drop sub frame... can anyone confirm?

That is unhelpful misinformation, you definitely do need to lower the subframe, regardless of OEM bar or not.]...

Thank you SO much for this! I'll be doing this in the next couple months as I just got my car back after 5.5 months in the body shop.

Cheers!

[bimmer_6uy]

thank you for the DIY Mr walker Ill be doing my sway bars front and end this week!