[The Nightman]

This thread got me curious so I looked up the torque spec on the sway bar bracket nuts and it's only 16 ftlb. I'm surprised my studs haven't broken yet...

Also, the end link nuts are 43 ftlb.

[BB_cuda]

I removed front sway bar today. There was very little torque from the factory. I will go real easy when the M3 bar goes in.

[Prev]

Originally Posted by slinkygn

So it seems like the hardest part of this is getting the remainder of the stud out... at least it's proving that way for me, anyway :/ It looks like this was done without actually removing the subframe, right? I can't seem to get enough force behind the punch upside-down to get that sucker off. It's driving me bonkers! Any suggestions?

I recently had this problem. Got pissed off with it, so gave it a few big smacks with a hammer and it popped out the top.

My repair was a lot more gash compared the bloke above. But I got a bolt and nut and after much swearing bolted it. If its the hole nearer the back of the car like me then it was a PITA. But a ratchet wrench instead of a normal wrench made all the difference.

[BB_cuda]

With a needed torque of only 16 lb-ft, I was nary going to trust my lb-ft range 1/2" drive Craftsman clicker. They just don't do well down that low in there range. I think 20 is the minimum anyway. I have 3/8" drive in-lb range Craftsman clicker type that goes up to 250 in-lb. 16 lb-ft converts to 192 in-lb. So, I tried the smaller torque wrench today. I went reeeaaalll easy with it. I never got it to click but did not go very hard at all. I know the rubber bushings are compressing but am paranoid to become another statistic in this thread.

Should I go get a beam type T-wrench?

[spitpilot]

Originally Posted by dbjb

Took some more images. I now need to source this "blind rivet bolt" or find a local welder. Opinions and recommendations welcome!

Here's a breakdown...

1) Overall image. As you can see, the bar has begun to pull away from the subframe. Meaning, I need to get this fixed ASAP.

2) Top of rear stud. The rear stud is accessible from the top.

3) Severed front stud.

4) The subframe is about 5mm thick but I can't get my finger on the top portion (blue) because of the subframe's form (red)

5) Mirror showing severed stud thread and top.

Looking at the broken off area...it appears to me that there is a wider part just below the aluminum plate...maybe a swaged in fitting that a stud was turned into?...Try vice grips on the broken threaded portion and see if it turns..use some "PB Blaster" a few times first to make sure if it's threaded in it's not siezed up...I just replaced my bushings and as I recall the torque on these is very low..I have 3 torque wrenches..one for inch pounds, one for 10-50 ft lbs and one for HD torque...you try to torque something requiring 5-10 ft lbs with a 50-200 ft lb wrench you're asking for trouble...don't ask how I know...in my youth I snapped off my share of tiny studs (think 4 mm Alfa water pump mounting..had to pull the radiator to get things fixed...taught me a lesson!)

[slinkygn]

Originally Posted by Prev

I recently had this problem. Got pissed off with it, so gave it a few big smacks with a hammer and it popped out the top.

As a matter of fact, that is *exactly* what ended up working for me. Amazing what a little bit of pissed-off will do for a situation!

Meant to take photos, but of course didn't. Turned out really, really well in the end. I'll try to remember to take some shots next time I've got her up on a lift; I have to drop the oil pan next time out anyway so that sway bar will definitely be coming off :/

Oh, and that seemingly swaged-in portion mentioned earlier is just the head of the press-fit stud; you can see on the other side the "scar" on the sheet aluminum from the stud press. That seemingly got pressed into that bit of sheet aluminum much like studs get pressed into hubs, and then that was all welded onto the rest of the subframe. I think the rivnut approach here is likely the most structurally sound solution available for this problem, bar none. I'm really happy with the results.

[slinkygn]

Originally Posted by E92fanboy

I also recently snapped one of these off. This thread looks like a lifesaver, but I had one question. What size is the Rivet Nut?

Just get that exact part: 51718175003. It's an M8 rivnut, but lower-profile than a standard M8 rivnut - I know because I bought an M8 rivnut from my hardware store first and it was different enough to where I (fortunately) held off until I could order and receive the genuine article.

Instead of then bolting the bushing bracket in, I got one of these off of McMaster-Carr:
https://www.mcmaster.com/#99067a113/=18ofn23

I may have actually been able to get away with using the 25mm instead of the 50mm, in retrospect. I screwed that sucker as far in as it would go, I think, with that contamination-resistant orange-red "red" Loctite (because I'm an overkill kind of guy) and it still protruded just a slight bit more than the other stud. I didn't mind; to me having it screw in until it hit the other bit of aluminum made it feel more secure somehow, and outside of the slightly greater length you can barely even tell that area was worked on.

(More overkill: I also smeared some JB Weld onto the outside of that rivnut before pressing it in. Why not, right?)

[AWDBooSTIn90]

Originally Posted by slinkygn

I just had this problem myself. That blind nut seems like a really elegant, professional-looking solution.

That said, I just ran into this video while looking for a solution for this and thought folks that had/are having this problem would be interested. Apparently there are other companies than this brand that have a product like this now, but this is the first I'd seen of it.

Full disclosure: I don't work or own any part of this company or any other that does this to my knowledge, and frankly had never even seen anything like this before.

I'm thinking about calling around to some metal work shops in the area to see if they have anything like this. (Maybe after I find some shear-strength specs, which I haven't yet -- but that video sure does seem to make it look sufficient.) What do you guys think?

Edit: just checked -- that particular tool will specifically do studs up to 5/16"/M8, which is exactly the size of that bushing mount stud that sheared off. I've seen other guns like it, but they all seem to just do thin 2/3mm pins, mostly to pull on for body work.

Edit 2: Since now it sounds like I'm plugging that original machine in the video, and I *hate* plugs masquerading as real posts, I found another machine that can do the same (including up to M8):

This looks like a tool i seen on wheel dealers lol. they weld the studs/pins to the sheet metal body to pull dents and accident damage out. Same concept to weld a legit permanent stud on, i guess.


OP glad you got this fixed! Also convenient that bmw dealers carry it because i don think a hardware store would have that, esp in a Metric Thread.

I've used similar products at work, fastening electrical component's to various surfaces. Amazing how well they work.

[andreu12qw]

This is what the forums are all about! Just had this happen to me, just on the other side, and was able to punch out the broken stud for a hex head cap screw and nut. Thought for sure my car would be down for weeks after it happened this past Sunday but thanks to threads like this I took my car out this morning for a nice sunrise drive. Thank you guys!

[mweisdorfer]

Originally Posted by dbjb

Many thanks to you all!!

Just finished the repair after picking up the last two parts at my local dealership. Need to shower so I'll let the images tell the story.

Was the black bolt you used a special m8 hex bolt? Where did you get it?

Please Advise

[mweisdorfer]

Originally Posted by mweisdorfer

Was the black bolt you used a special m8 hex bolt? Where did you get it?

Please Advise

The same exact bolt on both sides is problematic for me. However, the bolt is not busted. The nut will not loosen from the bolt nor tighten to any degree. It just turns but the bolt stays solid & doesn't move.

I'm thinking I'm going to have to remove the sway bar & bushings from the metal casing. Then cut away most of the metal casing away (it will be bent up by this point trying to get the bushing out) with a set of tin snips, dremmel, or sawzall. I'll then have to cut off both bolts, punch them out & install the blind rivet nut.

[whyzee125]

Great repair!

[feuer]

Or instal with regular bolt and nut.

[drymite]

I believe you can only do a regular bolt and nut on the 2 stud closer to the rear. The front studs aren't easily accessible from the top unless you drop the subframe.
I had same issue recently i used a regular nutsert and a double threaded m8 stud instead .

[Fishspeaker]

Originally Posted by drymite

I believe you can only do a regular bolt and nut on the 2 stud closer to the rear. The front studs aren't easily accessible from the top unless you drop the subframe.
I had same issue recently i used a regular nutsert and a double threaded m8 stud instead .

I originally went with the rivet method folks had suggested to deal with the front stud break however one rivet eventually broke but in a twist of European irony I discovered I was able to bend a thin Ikea wrench and use it to hold a nut in place between the two subframe plates on the front stud area to bolt/nut attach stabilizer support. Used a piece of packaging tape on top to hold the nut in place while I bolted in from the bottom.



UPDATE: looks like my pix didn’t go through so uploaded to this album:
https://www.e90post.com/forums/album.php?albumid=20094

Used a bolt and nut from a mini bike engine mount I had laying around which fit perfectly into the wrench.

[andreu12qw]

Originally Posted by Fishspeaker

I originally went with the rivet method folks had suggested to deal with the front stud break however one rivet eventually broke but in a twist of European irony I discovered I was able to bend a thin Ikea wrench and use it to hold a nut in place between the two subframe plates on the front stud area to bolt/nut attach stabilizer support. Used a piece of packaging tape on top to hold the nut in place while I bolted in from the bottom.



UPDATE: looks like my pix didn’t go through so uploaded to this album:
https://www.e90post.com/forums/album.php?albumid=20094

Used a bolt and nut from a mini bike engine mount I had laying around which fit perfectly into the wrench.

Genius!!

The Bently manual lists two torque specs. I when with the higher spec and found out the hard way that I was wrong. I broke the stud that had more access so i just threw a nut on the back and a bolt from the bolt bin.

[09BSME92N51]

I've been a long time lurker and this forum has helped me so many times that I had to finally make an account to thank OP and others for sharing their experiences and info. Between the various forums and youtube, I don't know how much money I've saved on both my cars because of all the people willing to seek and share info. It's a beautiful thing

I have hope again lol I've finally been trying to do some of my own work on my e92 328 and had the same issue of overtorqueing that front bracket nut and broke the stud. I thought it was hopeless so I called my cousin's mechanic to see if he could bail me out, but he was more concerned with getting the stud itself out.

That part was easy and came out with a few good taps of a hammer. Ordered that blind rivet and can't wait to try this!