I've got a 98 ZJ pushing 200k. Over the years I am sure the front sway bar brackets have been removed several times during service. The sway bar mounting bolts hold the bracket, the bushing and the bar to the unibody "frame" rail. The nuts are welded to the inside of the frame rail. The mounting bolts are coarse thread and a bit unique in that they are a hybrid; part carriage bolt, part lag bolt. Somewhere along the line someone crossed some of these threads, possibly careless use of an air gun. This has caused the nuts to deteriorate to the point where the sway bar mounts will not stay torqued down. I have had to insert thin wire into the nuts before I insert the bolts as a way to take up the extra space. It is to the point now where the bolts refuses to stay tight.
Has anyone run into this situation? Is there a proven solution? Thanks in advance for any suggestions.
I honestly don't know what to tell you. I cross-threaded one of my nuts in the unibody when I was replacing the swaybar bushings and installing a KOR steering brace. The bolt seemed sturdy enough, but I could tell it wasn't right. It had made a sound like it'd not torqued down all the way but instead snapped the nut from the body, so it was spinning freely. I decided to drive home, just a mile, and worry about it the next day. Surely this would be okay? The bolt disappeared. I spent my lunch hour the next day, and after I got off work, searching all over town for a bolt I could replace it with. No one on JF had any real suggestions for what I considered was a broken off nut inside the 'frame.'
It turns out that I was able to find a bolt, which is rusting so must not have been treated like it should have been(darn the luck) and the nut was still intact. I had been told I'd need to have someone cut out a hole big enough in the 'frame' to get a new nut inside and be able to torque down a bolt to hold the swaybar bracket down. In your case, you might need to do both this and drill out the current nut that's stripped. Then just place a new nut atop the old one. I'm not sure if you could break the old one free inside the frame itself, but setting one on top should work for this. I don't think it'd be prone to break with the old nut helping to hold the bolt in place, as long as you torqued it all down well. But cutting into the unibody is an iffy consideration.
Thanks for the quick responses. The idea of cutting a hole large enough to provide access to weld in new nuts seems counterproductive. The design of the "captured" nut system shows that vehicles are designed for production and damn the person who has to service them down the line.
Ratmonkey, talk about a "why didn't I think of that" moment. I am asking the following because I do not weld. Did you use a particular type of stud or just some threaded rod you had laying around---I might lean toward hardend fine thread/grade 8. Is welding the outside circumference of a stud to the frame strong enough. Pardon my ignorance, but like I said, I do not weld.
Again thanks to both for relating your experience.
I drilled the hole/nut out enough to hammer in a socket head cap screw. Also counter sunk the surrounding area for more weld area and to keep the bead below the mounting surface.
A couple of the nuts are blind holes, found that or the hard way when chasing the threads. Hence the need for studs.
Pro tip, spray pam on the threads to keep spatter from screwing them up.
'97 zj 5.2, some stuff, some other suff, and some things that even work sometimes.
I am not sure exactly what a socket head cap screw is. Do you mean a bolt with a head that takes an allen key? Thanks again for your help. These are the type of repairs that make it such a challenge to keep an older, high mileage ride in good shape. This loose sway bar clunks around so much that it sounds like the entire front end is going to fall off the chasis. Its not that these types of jobs are that difficult, just a pita.
This Sunday the exact same thing happened to me. I was thinking of drilling a hole threw the bottom of the frame and then run 5/8 all thread grd8 then lock washer and 1 1/16 bolts. Like you said it would lose a lot of strength and most likely bend the frame if I cut it where the bolt is.
I had something similar happen just about a month ago when i went to change my bushings also.
Long story short, but:
Bolts were rusted in and rounded off
Had to heat up with oxy/acel torch and beat a socket on them
used impact to get bolts out
The one bolt head broke (stud stuck in frame rail)
drilled it out, and attempted to tap it out to the next size...
Then the damn tap broke!
spent about 3 hours in the snow covered ground with an air chisel and die grinder with carbide bit trying to remove the tap from the framerail.
Finally got it out, but had a huge hole, so I drilled and tapped it out to 3/4" and its holding fine. I was worried I'd have it drilled out too far and the nut in the frame wouldn't hold but it did well.
If I were you, I'd just try to drill and tap it out to the next size. If you don't like that idea, just weld a stud on like suggested
Thanks for the additional replies. I was wondering if anyone has tried (or even considered) trying to fix this problem using a helicoil (sp?). You would have to drill out the hole to a larger size but in theory you be adding material back in with the helicoil. My only hands on experience with helicoils has been on caliper mounting bolts and they worked great in that application. I also had a shop put one in a spark plug hole where the plug came loose and blew out and that repair was also successful.
Ratmonkey, if you see this I would be interested in your thoughts on the helicoil idea since, after viewing you build thread, I am humbled by you abilities.
Thanks again to all who responded. I hope to have the opportunity to return the favor in the future.
I was going to replace the sway bar bushings on my ZJ today but ended up selling the hardtop and full doors from my YJ. I will try to replace the bushings tomorrow. It looks as if it will be easier on my ZJ as there is no rust on it.
1973 Dodge Dart Sport
1980 Honda CB900c
i broke one of my sway bar links trying to get the bolt off when i put my 2in. bb in. i bought new sway bar links and i had to cut the bottom bolts off to get them off. then to get the head out i had to use a 3lb sledge and a chisel. i just went down to my local hard ware store and bought the biggest grade 8 bolt that would fit through the metal sleeve inside the bushing. i also bought regular washers for each end of the bolt and a lock washer for one side. i filed out the hole in the bracket a little to make it a perfect fit.
edit: if you want to put in new sway bar links while your at it, theyre 15 bucks each at auto zone. come with everything but that bottom bolt.