I'm replacing my subframe bushings soon, and had another question. Has anybody had trouble with the cage nuts breaking, or are they pretty solid? I haven't loosened the bolts up yet, but I want to make sure they're not going to break on me. My car has very little frame and underbody rust, so I think the mounting plates themselves should be ok. I already ordered new j-nuts and bolts for the rear in anticipation of them breaking. I am going to do the rear spring replacement and bushings all at the same time.


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Shawn Peterson
1969 Z28, 406SB
http://www.geocities.com/corsican69

I just did them on my 69 RS. I did have rust and had to weld in repair plates. Not bad, I made them from 1/4" steel plate. Much cheaper and a bit thicker than the ones offered from Classic, Rick's etc. Now to the good part. Both middle bolts broke off even though I had soaked them for days. I was able to pry the cages off with a pry bar fairly easily. Then I put everything back together with a washer and nut - grade 8. Since I had my driver's fender off, access wasn't a problem. With the fender on, I might have had to remove the brake lines from the master cylinder to get leverage room. The passenger side was easy. Hopefully, you will not have that problem. The rear bolts were easy to remove. Those open areas in the firewall are a real dumping ground for crap coming into the engine compartment.

Rick, could you tell what size the holes need to be for the middle subframe mounts. I need to build new ones myself, are they the same diameter as the rear ones? Thanks.

They were 1 1/2" which I did with a hole saw. Use ear plugs! The solid mounts I put in were about 1/16 smaller so there was a little slop. Since my subframe holes were rotted, I don't know how precise the opening was. I suspect the stock rubber mounts squish out and fill the opening tightly. My bushings were from Global West who recommended 100 foot pounds of torque to tighten so I'm comfortable they won't shift.