Broken bolts on Lower Control Arm?

[veetwelve]

If you are reading this I am sure that you have come across the very poor design in the lower control arm mounting bolts.
They are spot welded to the inside of the unibody and are unaccessable.
When I was doing my job the nut on the inside of the unibody broke free... what to do now...

Here is what I had to do.
Cut hole in the inside of the fender well... There is also an inner panel that will have to be drilled or cut through.
It has to have a hole big enough to pull the old cut off nut and bolt out through, as well as be big enough to get a boxed end wrench through when it comes to putting your new Grade 8 bolt and nut on.
I sprayed rubberized undercoating on the inside hole that was drilled out before I folded the metal plate back over for welding.

Weld your hole up, grind, sand and spray with undercoating.

We chose to close the hole back up with the assumption that we would never have to get in there again. You could alternativley cut the plate completely out and get some kind of big rubber plug to put back in the hole if you are looking for future access.

I hope that this helps someone out there.!!

Cheers and happy Auto Repair

 

[slavrenz]

This is helpful info - which bolt on the control arm was that that broke? I am having trouble getting the super short rear bracket bolt to tighten correctly, and I fear the nut may have separated from the chassis.

 

[veetwelve]

It was the outer most bolt. It was the bolt that was on the side of the bracket that had only 1 bolt. I know which bolt you are talking about and I would almost guarantee that you have broken the nut loose from the chassis. The process we used above will allow you access to all 3 of those bracket bolts that are in there. You may have to make the hole a bit larger to get further back in to that last nut, but you will be able to.

Just cut the head of the bolt with a zip disk and pull the rest out thru the hole you cut in the fender well..

Good luck

 

[slavrenz]

Thanks man. Just out of curiosity, what did you use to cut that hole in the metal? And also what kind of torch do you have to use to weld that covering back on? I'm pretty good with cars, but I don't really have any heavy duty tools, and I'm sure a shop would kill me with labor charges.

Also, it's weird, but even though the bolt won't tighten, I have no problem backing it out of the hole. The bolt will get sort of tighten (about 25-30 ft-lbs) and then start spinning loose again, then get tight again, then loose, etc.

Does this still sound like the nut is loose, or do you think something might just be wrong with the threads on the nut?