Today i put in a Hotchkis 19mm rear sway bar and during the installation, while tightening the bracket down to hold the bar to the rear subframe, the bolt kept spinning in place and did not tighten to a stop. I don't know if it was stripped or cross-threaded or what, but it tightened to a point and then stopped tightening, but it kept spinning. When i tried to unscrew it, it just spun in place as it did when I was tightening it. So i continued the installation of the bar and since it was not coming out i drove on it, and it is fine for now. But now i am worried that it is going to fall off, so does anyone have any suggestions for what i should do? I looked up the bolt and it is a Hex bolt M8X12-8.8-ZNS3. I was thinking, since the back end protrudes out a little, that i could put a nut on the end to secure it in place, but i don't know what kind of nut to get. If anyone has any other solutions help would be appreciated. Thanks! Oh and the car drives great with the new sway bar, I have it on the middle setting now and it is great.

 

Should be a metric bolt, M8 size. I think the standard thread is 8x1.25mm, but I think there may be one or two other thread pitches available. A large hardware store, or auto parts store, or your local Caterpillar dealer should have a selection of metric nuts and bolts.

I'd try to remove the bolt--possibly pushing in on the back side as you're spinning it out, and maybe levering the head of the bolt outward as you spin it when you can't push on the end of the bolt. You can make sure you get a nut and bolt that match that way, and you can look to see if it's really the bolt or the weld-nut that is messed up.

You can run a tap of the same size through the bolt hole to chase the threads and clean them up, that should at least help some. But a nut on the back of the bolt (and a slightly longer bolt so you can get the nut all the way on it!) would not be the worst idea.

 

I tried to push the bolt out as i spun it, but it did not come out. It seems to be seated in there very securely, so i just put everything back together and will check to make sure it does not come off after driving. I drove on it tonight and it did not loosen at all so hopefully it stays that way. Thanks for the quick response!

 

You stripped a portion of the threads. When you're ready to fix it right, you'll need a heli-coil kit to repair the threads. The most labor intensive part is going to be getting access to that hole so you can drill it perfectly square. That might mean completely dropping the rear subframe out of the car The only other method I can think of is using a bolt and nut through the backside of where the swaybar bushing sits. It may not be drilled completely through though.

 

Thanks for the suggestion, I do not have the time to fix it now but maybe in the future i will be able to fix it. I was thinking about the nut through the backside, for that would be the easiest fix, and i will update you guys if i do that.