Stripped Rear Trailing arm bolts to body

[akhihamad]

Hello everyone,

Last weekend I got into an accident, and damaged the rear passenger side suspension.. two of the three bolts that hold the trailing arm to the body were forced out and stripped due to the impact. Did a little research and found information getting a time sert rethread kit, m12x1.5..




Sent from my iPhone using Tapatalk

[akhihamad]

Anybody have any experience with this before?


Sent from my iPhone using Tapatalk

[sapote]

Hello everyone,
.. two of the three bolts that hold the trailing arm to the body were forced out and stripped due to the impact.

Do you mean the "C" shape arm that mounted right below the right door trailing edge and front of the wheel well? I thought it has 4 bolts and not 3. these are adjusting bolts for the toe alignment. If the arm was pulled off by the impact, make sure the chassis mounting surface was not distorted too much or your Timesert fixed will not get the arm to align to spec. Pic of the said 3-bolt area? Did the wheel hit the curb in a slide?

[akhihamad]

Do you mean the "C" shape arm that mounted right below the right door trailing edge and front of the wheel well? I thought it has 4 bolts and not 3. these are adjusting bolts for the toe alignment. If the arm was pulled off by the impact, make sure the chassis mounting surface was not distorted too much or your Timesert fixed will not get the arm to align to spec. Pic of the said 3-bolt area? Did the wheel hit the curb in a slide?

yes the curb was hit in a slide, i’m pretty sure the mounting surface is okay as the bracket broke with one bolt left threaded on..
this is what I am referring to, where the bushing is mounted in the middle, and three bolts are bolted on to the chassis


Sent from my iPhone using Tapatalk

[elbert]

I probably wouldn't trust a Timesert or Helicoil for that. I think I would try to find someone to weld in a new pocket.

[akhihamad]

I probably wouldn't trust a Timesert or Helicoil for that. I think I would try to find someone to weld in a new pocket.

Could you give me more information on this pocket thing.. not sure how I would go about it


Sent from my iPhone using Tapatalk

[sapote]

two of the three bolts that hold the trailing arm to the body were forced out and stripped due to the impact.

Yes, they are the 3 bolts. Can you take pic of the 3 threaded holes that were damaged? Just want to see how thick is the threaded section. Is the mounting surface still flat or distorted? Timesert when use properly should be as strong as the stock threads.

[akhihamad]

Yes, they are the 3 bolts. Can you take pic of the 3 threaded holes that were damaged? Just want to see how thick is the threaded section. Is the mounting surface still flat or distorted? Timesert when use properly should be as strong as the stock threads.

Mounting surface looks flat.. tried to get photos of the surface as best as I could, as well as photos of the threads


Sent from my iPhone using Tapatalk

[robgill]

The “pocket” that that 3 bolt carrier bolts into is a piece that is spot welded into the chassis. You can replace it by drilling out the welds and welding in one sourced from a different chassis (maybe any e46??). I don’t think you can buy that part new.

[robgill]

From your pics it looks like your pocket is broken and would need to be welded up regardless of what you do with the threads.

[akhihamad]

how can you tell that the pocket looks broken? and if the pocket were to be fine, rethreading would be a solution correct?


Sent from my iPhone using Tapatalk

[Nuclear Rabbit]

Looks like your axle carrier panel might have shifted too (top right of first image, broken seam sealer). I've stripped one of my bolts similar to what you have (albeit not from accident damage) and was able to helicoil it with kit 554412. It torqued up to factory spec fine and also made it through an alignment shop no problem.

You might want to clean out those pockets really well and test the spot welds. There's a video floating around of a track M3 where the welds on one of the pockets fail and the trailing arm drops out in the middle of a race. Would imagine yours took some stress.

[T.J.]

Not going through insurance to fix? Seems like a costly repair between the quarter panel and whatever you find with the pocket.

[sapote]

Mounting surface looks flat.. tried to get photos of the surface as best as I could, as well as photos of the threads

Luckily the mounting pocket seems to be fine. How do you know the threaded holes are bad? 2 bolts were pulled out in the accident?

From the pics, I believe the female threads were compromised before the accident -- weaken by cross threaded previously. If this is true, you're lucky that the bolts were pulled out with the weak threads and avoid damaging the pocket if they were with good threads. I would drill out the bad threads, tap new threads and Timesert, not helicoil. I don't see any broken or distorted areas on the pocket.

[akhihamad]

Luckily the mounting pocket seems to be fine. How do you know the threaded holes are bad? 2 bolts were pulled out in the accident?

From the pics, I believe the female threads were compromised before the accident -- weaken by cross threaded previously. If this is true, you're lucky that the bolts were pulled out with the weak threads and avoid damaging the pocket if they were with good threads. I would drill out the bad threads, tap new threads and Timesert, not helicoil. I don't see any broken or distorted areas on the pocket.

yes, 2 bolts were pulled out due to accident.. but yeah I ordered a time sert kit off amazon, should be here monday, hopefully it works


Sent from my iPhone using Tapatalk