The nuts that are inside the frame that take the shackle-mount bolts are either rusted, shot, or spin. I've heard solutions where you can cut access holes in the frame to repair the inside nuts and then patch up the frame again. I was thinking of something better....
My thought was to drill a hole on top and bottom of the frame and weld a sleeve (a tube) right through the frame so this way I can now run a bolt from top to bottom and never worry about bad hidden nuts again. Anyone try this before? Does it make sense to do? Thoughts? Suggestions?
My CJ is frame-off right now so my only reservation with this technique is if the bolt head that would now be sitting on top of the frame may get in the way of something (again, I can't tell right now because my Jeep is in a million pieces), but besides the possible bolt head having room issues, I think this method would be the strongest and best way of doing it. Would love to hear your thoughts.
I had the exact same problem on my rear shackle mounts. My solution was a 1" hole saw. I drilled a hole in the side of the frame so I could easily access the old busted riv nut inside. I took a chisel and a hammer and knocked the riv nut out so I had a nice clean hole then used a new Grade 8 bolt nut and bolt to hold on the shackle. Nice thing about a 1" hole is you can stick a wrench in there and hold the nut from spinning so its not something you will need to worry about rusting or breaking off down the road. Another option is to just drill out the hole and tap it with a larger bolt.