Steering Rack leak

[HapaM3]

Hard lines leaking on your steering rack need the o-rings replaced. I replaced mine. BMW does not list o-rings. You need to purchase them elsewhere. Contact me if you need help. It's a not so hard DIY and the subframe does not need to be pulled in order to do the fix.

[thongvua]

Just realized my steering rack is leaking fluid as well. Do you have any instructions posted somewhere?

[kikkoman]

Originally Posted by thongvua

Just realized my steering rack is leaking fluid as well. Do you have any instructions posted somewhere?

Mine is also leaking from up top of the rack I think. Have you resolved your leak and if so mind sharing how?

[jfo122]

Also have a leaky steering rack. Would be interested in hearing about the o-ring solution.

[kikkoman]

I'm just thinking now about ordering remanufactured rack from rackdoctor. Anyone done rack replacement can share how difficult this job is? Is it a DIY or should be done at a shop? I can't find any write up online for our particular car for some reason.

[takrdown]

I just did this actually: ordered a rack from rackdoctor and did the DIY. It's not terribly hard.

The hardest part is cleaning up the mess the steering fluid leak made. The only hard part of the install is going to be difficult is trying to match the steering rack position on the old one to the replacement.

If it is too far off your alignment will be so out of wack you won't be able to make it to the shop so I would pay close attention (so close I used a micrometer from work to match and I was still off) to the alignment.

Get new bolts and nuts for the rack. I did not replace the o-rings on the hard lines...didn't realize there were any, but I did replace the copper washers for the hard lines going into the rack. If you go on real oem, they do not list the part number (they are blank) for those o rings. What I did was look at the real oem listing for the e82 1M. That car had the same exact steering rack as the M3 and they matched and fit perfectly.

Where you will need o-rings is the two o-rings on the servo controller. A new servo controller does not come on the rack doctor steering rack so you will have to use your old one. The problem I had was finding the right o-rings because the size isn't available anywhere. I'm kicking myself for not documenting it now.

I bought this kit from amazon:

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

I think what was included fit one of them and then I bought an assortment of o-rings from "The O-Ring Store" and obviously only ended up using a couple. The problem is that o-rings in kits tend to be too large for this application and you don't want them to be large. The servo controller should kind of click or snap back in...then the two screws just hold it in place. You shouldn't need to screw down on the o-rings to get it in there. This is the assortment I bought:

7 x 2mm X 18mm (NBR) Buna-N 70 Duro Metric O-Ring (N2.00X018) $0.56
5 x 1.5mm X 17mm (NBR) Buna-N 90 Duro Metric O-Ring (H1.50X017) $0.50
5 x 1.5mm X 18mm (NBR) Buna-N 70 Duro Metric O-Ring (N1.50X018) $0.50
5 x 1mm CS X 18mm ID (NBR) Buna-N 70 Duro Metric O-Ring (N1.00X018) $0.55
---------
Sub-Total: $2.11
USPS (First-Class™ Package Service): $6.13
Total: $8.24

If you have questions let me know. I have about 3-4K miles and no leaks so I guess I did it right...

[takrdown]

I have time to kill, so here are some of the parts you will probably want outside of the o-ring thing I talked about above:

-Upper(larger) banjo bolt: 32416852470
-Lower(smaller) banjo bolt: 32416781261

-(x1) Torx head bolt for steering rack column to coupling: 32306778609

-(x2) Gasket rings for smaller banjo bolt: 07119906464
-(x2) Gasket rings for larger banjo bolt: 07119906463

-(x2) Hex nut for mounting steering rack: 31356757707
-(x2) Torx Bolt for mounting steering rack: 32106773068

-(x2) Hex nut for mounting outer tie rod to wheel hub: 31106768886

The fit is tight, but outside of a new alignment, it's is very straight forward.

[kikkoman]

Thanks, takrdown, for the detail parts list regarding the rack replacement! I'm sure this will serve useful for all other members possibly looking into doing this job.

I still wished there was some kind of detail write-up with pics like many other DIY jobs that are available both in this forum and elsewhere even Youtube videos. I wonder if lack of DIY resources is attributed to not many failed racks on these cars or not many actually doing it.

[takrdown]

Originally Posted by kikkoman

Thanks, takrdown, for the detail parts list regarding the rack replacement! I'm sure this will serve useful for all other members possibly looking into doing this job.

I still wished there was some kind of detail write-up with pics like many other DIY jobs that are available both in this forum and elsewhere even Youtube videos. I wonder if lack of DIY resources is attributed to not many failed racks on these cars or not many actually doing it.

Absolutely no problem! In hindsight I wish I had done a detailed DIY. Maybe I can write something up from memory...

I guess the reason I wasn't scared to do this was that I had a hell of a time doing it on my 135 when I had to do it. That's a different story and I'm sure you can still find it on 1addicts. So I knew all the places I could get hung up, with the exception of that servo which the 135 rack doesn't have.

Things that will go a long way with this is patience and small hands which I don't have hahaha.

Let me know how I can help!

[kikkoman]

I still haven't made up my mind about doing this myself so I called around few local indy shops specializing on BMW and quotes were between $2-3k. I'm now leaning towards DIY so trying to get more details.

I've seen many videos and write-ups for other cars including regular E90 so what would be different for our M3 rack? Are there anything in particular that I should watch out for? Servo removal & install on the new rack seems pretty straightforward. The only real hang up I could think of is accessing the steering shaft to remove & reinstall to the coupler due to very tight spacing.

Obviously, the problem with this or any DIY job is once I get started there's really no turning back must commit and finish.

[takrdown]

Originally Posted by kikkoman

I still haven't made up my mind about doing this myself so I called around few local indy shops specializing on BMW and quotes were between $2-3k. I'm now leaning towards DIY so trying to get more details.

I've seen many videos and write-ups for other cars including regular E90 so what would be different for our M3 rack? Are there anything in particular that I should watch out for? Servo removal & install on the new rack seems pretty straightforward. The only real hang up I could think of is accessing the steering shaft to remove & reinstall to the coupler due to very tight spacing.

Obviously, the problem with this or any DIY job is once I get started there's really no turning back must commit and finish.

So I was able to access the hex bolt for the coupling next to the steering rack through the gaps in the drivers side wheel well to loosen it then you can just yank that sucker out. You might need some extensions and some creativity to get there, but that's what cheap harbor freight tools are for right. Haha.

Getting it back in was a little more difficult. Make sure you keep your steering wheel centered and line up the coupler. Then I used a long screwdriver to pry the collar back together (it takes some force) and then tighten the new hex bolt the same way you loosened the old one through the gaps in the wheel.

Could you post the diy's you have and I can point out any differences?

[takrdown]

Also these may help:

https://www.newtis.info/tisv2/a/en/e...g-unit/GLPYI8V

https://www.newtis.info/tisv2/a/en/e...rement/GTebPnF

https://www.realoem.com/bmw/enUS/sho...diagId=32_1738

https://www.realoem.com/bmw/enUS/sho...diagId=32_1734

[kikkoman]

More great detail info there! Thanks, takrdown.

If I do decide to go ahead with doing this myself I'll definitely put some kind of DIY together and send it to you for review/editing so we can collaborate to put something here for benefit of other members thinking of doing this in the future. Thanks again!

[takrdown]

Sounds great to me!! Hit me up if you decide to do it and have any snags (I'm sure something frustrating will happen). The torque specs are in those instructions too.

My buddy has a plaque above his desk that reads: "Every two hour job is one broken bolt away from being a three day ordeal."

Seems like every job on a BMW feels that way right?

[kikkoman]

Perhaps the last mental snag I'm now having is how best to make sure the new rack bolts up to the steering column EXACTLY how it's suppose to or how the old one was. I've read (yes I know we can't believe everything we read but...) being even one spline off can introduce bump steer.

Any steps (pre/post measurements, markings, etc.) that can be done to negate this as much as possible during installation of the new rack?

Related to this, in hindsight since you've already recently done this , what would be the quickest/easiest way to separate the old rack from the steering column and also during reinstallation.

[takrdown]

So as far as making the new rack line up the same way as the old rack, the procedure in the link below should help:

https://www.newtis.info/tisv2/a/en/e...rement/GTebPnF

I would take notes and picture before you break those outer tie rods...before you even move them off the inner tie rods.

I used a lever (pry bar/large screwdriver) stuck in between the column and the rack to both separate and move it back in. It's a beefy part so I wouldn't worry about breaking it.

One snag I just thought of, is there is no easy way to place the spline guide back onto the new rack from the old rack as the new one doesn't come with it. I'm talking about the black plastic thing.

So I guess I would do it like this:

1. Lock the steering wheel at dead center with bungy cord or something
2. Remove the steering rack assembly being careful not to turn the wheel at all or the steering rack after it has been removed.
3. Take your measurements like in the hyperlink, again not turning the steering rack at the column connection point at all (like you were turning the steering wheel if that makes sense).
4. Make as precise measurement as possible as to where the orientation of the black plastic spline guide thingy is on the old rack.
5. This is the point of no return so measure and remeasure everything: Turn the old rack all the way to the right and all the way to the left taking note of EXACTLY how many turns you turn in each direction to the stop.
6. Now turn the new one with pliers so that you can place it exactly in the orientation into dead center like on the old one.
7. Now you can move the plastic spline guide thingy and the two outer tie rods over to the new one matching the measurement you took on the old one. Don't worry so much about the orientation...worry about the measurement. those outer tie rods can bend a bit once into the hub...it's the measurement that's the important part.
8. Install the solenoid
9. Reinstall the new one being careful again to not change the orientation the steering column. No need to worry about the outer tie rods because they should be cranked down and bolted.

I think that's it for that part? It's the most stress inducing, and I can assure you that no matter how precise you are you will need an alignment.

[kikkoman]

UPDATE: Just couldn't find the time for DIY with work schedule and family vacation plan (traveling now) so I had a local shop do the replacement. My brother just picked up the car while I'm away but told me the steering now shakes and makes some kind of grinding noise when braking at freeway speed. He's taking it back to the shop for recheck.

The car didn't have any issues beside the rack leaking so what might be the most common issue for this shaking? I'm now regretting maybe I should have just waited and do this myself but too late for that now.

[takrdown]

Originally Posted by kikkoman

UPDATE: Just couldn't find the time for DIY with work schedule and family vacation plan (traveling now) so I had a local shop do the replacement. My brother just picked up the car while I'm away but told me the steering now shakes and makes some kind of grinding noise when braking at freeway speed. He's taking it back to the shop for recheck.

The car didn't have any issues beside the rack leaking so what might be the most common issue for this shaking? I'm now regretting maybe I should have just waited and do this myself but too late for that now.

It could be a lot of things but it sounds like a poor installation to me.

[kikkoman]

Turns out it was just the rotors not related to the rack installation. I had replaced front brake pads only couple of weeks before the rack replacement and sounds like I didn't bed them correctly. The shop probably just resurfaced them as my brother said the shaking is now gone. Hope to get back to driving the car again when I'm back.

[takrdown]

Originally Posted by kikkoman

Turns out it was just the rotors not related to the rack installation. I had replaced front brake pads only couple of weeks before the rack replacement and sounds like I didn't bed them correctly. The shop probably just resurfaced them as my brother said the shaking is now gone. Hope to get back to driving the car again when I'm back.

Awesome! I was hoping for an update

[icanturn]

Originally Posted by takrdown

Get new bolts and nuts for the rack.

Why? Are they stretch to yield?

Originally Posted by takrdown

I did not replace the o-rings on the hard lines...didn't realize there were any, but I did replace the copper washers for the hard lines going into the rack. If you go on real oem, they do not list the part number (they are blank) for those o rings. What I did was look at the real oem listing for the e82 1M. That car had the same exact steering rack as the M3 and they matched and fit perfectly.

Does anyone know where I can find the sizes for these? Real OEM doesn't show the end of the hardlines that connects to to the rack. I assume there are o-rings or a gasket there.

Originally Posted by takrdown

Where you will need o-rings is the two o-rings on the servo controller.

I think what was included fit one of them and then I bought an assortment of o-rings from "The O-Ring Store" and obviously only ended up using a couple

7 x 2mm X 18mm (NBR) Buna-N 70 Duro Metric O-Ring (N2.00X018) $0.56
5 x 1.5mm X 17mm (NBR) Buna-N 90 Duro Metric O-Ring (H1.50X017) $0.50
5 x 1.5mm X 18mm (NBR) Buna-N 70 Duro Metric O-Ring (N1.50X018) $0.50
5 x 1mm CS X 18mm ID (NBR) Buna-N 70 Duro Metric O-Ring (N1.00X018) $0.55

So which if these did you end up using? And where exactly?


My rack is leaking from the pinion seal at the top. I believe the fluid is trickling down from the top and covering the hardline "plate" as well, which at first was where I thought the leak was coming from (see pic). It still might be leaking from there and if im gonna have the rack out I wanna re-seal these just in case.

I was able to do some digging into the pinion seal. I found this info on it:

NOK (manufacturer)
20-30-5 (dimensions)
ZF 0770 080 538 (part number)
APO981E (manufacturing number?)
22 (no clue)

These are all the markings on the seal. I cannot find anyone who sells it though, which is a bit surprising considering its a NOK / ZF part.

This is the "plate" I mentioned earlier. If you look where the hex bolt is (side profile) you can see the small hardlines on the plate too. Just above this is the pinion seal, which you can barley make to if you know what to look for.

[Rino924]

Wanted to bump this. I think I have a leak on mine. Shop said not to be too concerned with it but if I have some free time and I start by replacing an o-ring where the small hard lines go in, it seems like a no brainer. Checking youtube, etc for more info but there isn't much. Really don't want to pull the rack out.